standalone_browser: Extract lacros selection handling from browser_util

This CL extracts lacros selection related methods/constants from
browser_util to //chromeos/ash/components/standalone_browser.

This is a part of an effort to cut the chrome dependency.

Bug: 336839132
Change-Id: I170ff1d68eb0aedcbd29902235b6fd1e9490e95d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5504636
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Reviewed-by: Nicolas Dossou-Gbété <dgn@chromium.org>
Commit-Queue: Eriko Kurimoto <elkurin@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1295382}

chrome/browser/about_flags.cc

@@ -288,6 +288,7 @@
 #include "chromeos/ash/components/assistant/buildflags.h"
 #include "chromeos/ash/components/memory/swap_configuration.h"
 #include "chromeos/ash/components/standalone_browser/lacros_availability.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "chromeos/ash/components/standalone_browser/standalone_browser_features.h"
 #include "chromeos/ash/services/assistant/public/cpp/features.h"
 #include "chromeos/constants/chromeos_switches.h"
@@ -1074,11 +1075,11 @@ const char kProjectorServerSideSpeechRecognition[] =
 const FeatureEntry::Choice kLacrosSelectionChoices[] = {
     {flags_ui::kGenericExperimentChoiceDefault, "", ""},
     {flag_descriptions::kLacrosSelectionStatefulDescription,
-     crosapi::browser_util::kLacrosSelectionSwitch,
+     ash::standalone_browser::kLacrosSelectionSwitch,
-     crosapi::browser_util::kLacrosSelectionStateful},
+     ash::standalone_browser::kLacrosSelectionStateful},
     {flag_descriptions::kLacrosSelectionRootfsDescription,
-     crosapi::browser_util::kLacrosSelectionSwitch,
+     ash::standalone_browser::kLacrosSelectionSwitch,
-     crosapi::browser_util::kLacrosSelectionRootfs},
+     ash::standalone_browser::kLacrosSelectionRootfs},
 };
 
 const char kLacrosSelectionPolicyIgnoreInternalName[] =
@@ -11335,8 +11336,8 @@ bool ShouldSkipConditionalFeatureEntry(const flags_ui::FlagsStorage* storage,
   }
   // Skip lacros-selection if it is controlled by LacrosSelection policy.
   if (!strcmp(kLacrosSelectionInternalName, entry.internal_name)) {
-    return crosapi::browser_util::GetCachedLacrosSelectionPolicy() !=
+    return ash::standalone_browser::GetCachedLacrosSelectionPolicy() !=
-           crosapi::browser_util::LacrosSelectionPolicy::kUserChoice;
+           ash::standalone_browser::LacrosSelectionPolicy::kUserChoice;
   }
 
   if (!strcmp(kPreferDcheckInternalName, entry.internal_name)) {

chrome/browser/ash/crosapi/browser_launcher.cc

@@ -49,6 +49,7 @@
 #include "chrome/common/chrome_features.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/logging_chrome.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "chromeos/crosapi/cpp/crosapi_constants.h"
 #include "chromeos/crosapi/mojom/crosapi.mojom-shared.h"
 #include "chromeos/dbus/constants/dbus_switches.h"
@@ -376,7 +377,7 @@ base::LaunchOptions CreateLaunchOptions() {
   return options;
 }
 
-void SetUpEnvironment(browser_util::LacrosSelection lacros_selection,
+void SetUpEnvironment(ash::standalone_browser::LacrosSelection lacros_selection,
                       base::LaunchOptions& options) {
   // If Ash is an unknown channel then this is not a production build and we
   // should be using an unknown channel for Lacros as well. This prevents Lacros
@@ -702,12 +703,13 @@ std::vector<base::FilePath> BrowserLauncher::GetPreloadFiles(
   return paths;
 }
 
-void BrowserLauncher::Launch(const base::FilePath& chrome_path,
+void BrowserLauncher::Launch(
-                             bool launching_at_login_screen,
+    const base::FilePath& chrome_path,
-                             browser_util::LacrosSelection lacros_selection,
+    bool launching_at_login_screen,
-                             base::OnceClosure mojo_disconnection_cb,
+    ash::standalone_browser::LacrosSelection lacros_selection,
-                             bool is_keep_alive_enabled,
+    base::OnceClosure mojo_disconnection_cb,
-                             LaunchCompletionCallback callback) {
+    bool is_keep_alive_enabled,
+    LaunchCompletionCallback callback) {
   auto* params = new LaunchParamsFromBackground();
 
   // Represents the number of tasks to complete before starting launch. If we
@@ -801,7 +803,7 @@ LaunchParams BrowserLauncher::CreateLaunchParamsForTesting(
     std::optional<int> startup_fd,
     std::optional<int> read_pipe_fd,
     mojo::PlatformChannel& channel,
-    browser_util::LacrosSelection lacros_selection) {
+    ash::standalone_browser::LacrosSelection lacros_selection) {
   return CreateLaunchParams(chrome_path, params, launching_at_login_screen,
                             startup_fd, read_pipe_fd, channel,
                             lacros_selection);
@@ -880,7 +882,7 @@ void BrowserLauncher::LaunchProcess(
     const base::FilePath& chrome_path,
     std::unique_ptr<LaunchParamsFromBackground> params,
     bool launching_at_login_screen,
-    browser_util::LacrosSelection lacros_selection,
+    ash::standalone_browser::LacrosSelection lacros_selection,
     base::OnceClosure mojo_disconnection_cb,
     bool is_keep_alive_enabled,
     LaunchCompletionCallback callback) {
@@ -949,7 +951,7 @@ LaunchParams BrowserLauncher::CreateLaunchParams(
     std::optional<int> startup_fd,
     std::optional<int> read_pipe_fd,
     mojo::PlatformChannel& channel,
-    browser_util::LacrosSelection lacros_selection) {
+    ash::standalone_browser::LacrosSelection lacros_selection) {
   // Static configuration should be enabled from Lacros rather than Ash. This
   // vector should only be used for dynamic configuration.
   // TODO(crbug.com/40729628): Remove existing static configuration.

chrome/browser/ash/crosapi/browser_launcher.h

@@ -18,9 +18,9 @@
 #include "base/process/process.h"
 #include "base/time/time.h"
 #include "base/types/expected.h"
-#include "chrome/browser/ash/crosapi/browser_util.h"
 #include "chrome/browser/ash/crosapi/crosapi_id.h"
 #include "chrome/common/channel_info.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "components/nacl/common/buildflags.h"
 #include "components/policy/core/common/values_util.h"
 #include "mojo/public/cpp/platform/platform_channel.h"
@@ -144,7 +144,7 @@ class BrowserLauncher {
   // completion.
   void Launch(const base::FilePath& chrome_path,
               bool launching_at_login_screen,
-              browser_util::LacrosSelection lacros_selection,
+              ash::standalone_browser::LacrosSelection lacros_selection,
               base::OnceClosure mojo_disconnection_cb,
               bool is_keep_alive_enabled,
               LaunchCompletionCallback callback);
@@ -190,7 +190,7 @@ class BrowserLauncher {
       std::optional<int> startup_fd,
       std::optional<int> read_pipe_fd,
       mojo::PlatformChannel& channel,
-      browser_util::LacrosSelection lacros_selection);
+      ash::standalone_browser::LacrosSelection lacros_selection);
 
   // Creates postlogin pipe fd and returns the read fd. This is used to test
   // ResumeLaunch. Note that the reader is on the same process and does not
@@ -244,7 +244,7 @@ class BrowserLauncher {
   void LaunchProcess(const base::FilePath& chrome_path,
                      std::unique_ptr<LaunchParamsFromBackground> params,
                      bool launching_at_login_screen,
-                     browser_util::LacrosSelection lacros_selection,
+                     ash::standalone_browser::LacrosSelection lacros_selection,
                      base::OnceClosure mojo_disconnection_cb,
                      bool is_keep_alive_enabled,
                      LaunchCompletionCallback callback);
@@ -256,7 +256,7 @@ class BrowserLauncher {
       std::optional<int> startup_fd,
       std::optional<int> read_pipe_fd,
       mojo::PlatformChannel& channel,
-      browser_util::LacrosSelection lacros_selection);
+      ash::standalone_browser::LacrosSelection lacros_selection);
 
   // Launches a process , which is executed in `LaunchProcess`.
   // This is also used for unittest.

chrome/browser/ash/crosapi/browser_launcher_unittest.cc

@@ -33,6 +33,7 @@
 #include "chrome/test/base/testing_browser_process.h"
 #include "chrome/test/base/testing_profile_manager.h"
 #include "chromeos/ash/components/login/login_state/login_state.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "chromeos/ash/components/system/fake_statistics_provider.h"
 #include "chromeos/ash/components/system/statistics_provider.h"
 #include "chromeos/crosapi/cpp/crosapi_constants.h"
@@ -253,7 +254,7 @@ TEST_F(BrowserLauncherTest, Launch) {
 
   constexpr bool launching_at_login_screen = false;
   browser_launcher()->Launch(lacros_path, launching_at_login_screen,
-                             browser_util::LacrosSelection::kRootfs,
+                             ash::standalone_browser::LacrosSelection::kRootfs,
                              /*mojo_disconneciton_cb=*/{},
                              /*is_keep_alive_enabled=*/false,
                              future.GetCallback());
@@ -284,7 +285,7 @@ TEST_F(BrowserLauncherTest, LaunchAtLoginScreen) {
 
   constexpr bool launching_at_login_screen = true;
   browser_launcher()->Launch(lacros_path, launching_at_login_screen,
-                             browser_util::LacrosSelection::kRootfs,
+                             ash::standalone_browser::LacrosSelection::kRootfs,
                              /*mojo_disconneciton_cb=*/{},
                              /*is_keep_alive_enabled=*/false,
                              future.GetCallback());
@@ -347,7 +348,7 @@ TEST_F(BrowserLauncherTest, ShutdownRequestedDuringLaunch) {
   // screen.
   constexpr bool launching_at_login_screen = false;
   browser_launcher()->Launch(base::FilePath(), launching_at_login_screen,
-                             browser_util::LacrosSelection::kRootfs,
+                             ash::standalone_browser::LacrosSelection::kRootfs,
                              /*mojo_disconneciton_cb=*/{},
                              /*is_keep_alive_enabled=*/false,
                              future.GetCallback());

chrome/browser/ash/crosapi/browser_loader.cc

@@ -20,7 +20,6 @@
 #include "base/task/task_traits.h"
 #include "base/task/thread_pool.h"
 #include "base/values.h"
-#include "chrome/browser/ash/crosapi/browser_util.h"
 #include "chrome/browser/ash/crosapi/lacros_selection_loader.h"
 #include "chrome/browser/ash/crosapi/lacros_selection_loader_factory.h"
 #include "chrome/browser/ash/crosapi/rootfs_lacros_loader.h"
@@ -95,9 +94,9 @@ bool BrowserLoader::WillLoadStatefulComponentBuilds() {
 
   // If the lacros selection is forced by the user or by policy to rootfs it
   // will always be loaded and stateful component manager builds are ignored.
-  std::optional<browser_util::LacrosSelection> lacros_selection =
+  std::optional<ash::standalone_browser::LacrosSelection> lacros_selection =
-      browser_util::DetermineLacrosSelection();
+      ash::standalone_browser::DetermineLacrosSelection();
-  if (lacros_selection == browser_util::LacrosSelection::kRootfs) {
+  if (lacros_selection == ash::standalone_browser::LacrosSelection::kRootfs) {
     return false;
   }
 
@@ -181,21 +180,21 @@ void BrowserLoader::LoadNow(LoadCompletionCallback callback) {
   // If the LacrosSelection policy or the user have specified to force using
   // stateful or rootfs lacros-chrome binary, force the selection. Otherwise,
   // load the newest available binary.
-  if (std::optional<browser_util::LacrosSelection> lacros_selection =
+  if (std::optional<ash::standalone_browser::LacrosSelection> lacros_selection =
-          browser_util::DetermineLacrosSelection()) {
+          ash::standalone_browser::DetermineLacrosSelection()) {
     // TODO(crbug.com/40213424): We should check the version compatibility here,
     // too.
     switch (lacros_selection.value()) {
-      case browser_util::LacrosSelection::kRootfs:
+      case ash::standalone_browser::LacrosSelection::kRootfs:
         rootfs_lacros_loader_ = factory_->CreateRootfsLacrosLoader();
         SelectRootfsLacros(std::move(callback), LacrosSelectionSource::kForced);
         return;
-      case browser_util::LacrosSelection::kStateful:
+      case ash::standalone_browser::LacrosSelection::kStateful:
         stateful_lacros_loader_ = factory_->CreateStatefulLacrosLoader();
         SelectStatefulLacros(std::move(callback),
                              LacrosSelectionSource::kForced);
         return;
-      case browser_util::LacrosSelection::kDeployedLocally:
+      case ash::standalone_browser::LacrosSelection::kDeployedLocally:
         NOTREACHED();
         std::move(callback).Run(base::FilePath(),
                                 LacrosSelection::kDeployedLocally,

chrome/browser/ash/crosapi/browser_loader.h

@@ -17,7 +17,7 @@
 #include "base/sequence_checker.h"
 #include "base/time/time.h"
 #include "base/version.h"
-#include "chrome/browser/ash/crosapi/browser_util.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 
 namespace component_updater {
 class CrOSComponentManager;
@@ -27,7 +27,7 @@ namespace crosapi {
 
 class LacrosSelectionLoader;
 class LacrosSelectionLoaderFactory;
-using browser_util::LacrosSelection;
+using ash::standalone_browser::LacrosSelection;
 
 // Manages download of the lacros-chrome binary.
 // This class is a part of ash-chrome.

chrome/browser/ash/crosapi/browser_loader_unittest.cc

@@ -19,11 +19,11 @@
 #include "base/test/scoped_command_line.h"
 #include "base/test/test_future.h"
 #include "base/version.h"
-#include "chrome/browser/ash/crosapi/browser_util.h"
 #include "chrome/browser/ash/crosapi/lacros_selection_loader.h"
 #include "chrome/browser/ash/crosapi/lacros_selection_loader_factory.h"
 #include "chrome/browser/component_updater/cros_component_manager.h"
 #include "chromeos/ash/components/standalone_browser/browser_support.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "components/policy/core/common/policy_map.h"
 #include "components/policy/policy_constants.h"
 #include "content/public/test/browser_task_environment.h"
@@ -189,25 +189,25 @@ class FakeLacrosSelectionLoaderFactory : public LacrosSelectionLoaderFactory {
 class ScopedLacrosSelectionCache {
  public:
   explicit ScopedLacrosSelectionCache(
-      browser_util::LacrosSelectionPolicy lacros_selection) {
+      ash::standalone_browser::LacrosSelectionPolicy lacros_selection) {
     SetLacrosSelection(lacros_selection);
   }
   ScopedLacrosSelectionCache(const ScopedLacrosSelectionCache&) = delete;
   ScopedLacrosSelectionCache& operator=(const ScopedLacrosSelectionCache&) =
       delete;
   ~ScopedLacrosSelectionCache() {
-    browser_util::ClearLacrosSelectionCacheForTest();
+    ash::standalone_browser::ClearLacrosSelectionCacheForTest();
   }
 
  private:
   void SetLacrosSelection(
-      browser_util::LacrosSelectionPolicy lacros_selection) {
+      ash::standalone_browser::LacrosSelectionPolicy lacros_selection) {
     policy::PolicyMap policy;
     policy.Set(policy::key::kLacrosSelection, policy::POLICY_LEVEL_MANDATORY,
                policy::POLICY_SCOPE_USER, policy::POLICY_SOURCE_CLOUD,
                base::Value(GetLacrosSelectionPolicyName(lacros_selection)),
                /*external_data_fetcher=*/nullptr);
-    browser_util::CacheLacrosSelection(policy);
+    ash::standalone_browser::CacheLacrosSelection(policy);
   }
 };
 
@@ -321,11 +321,11 @@ TEST_F(BrowserLoaderTest, OnLoadVersionSelectionSameVersions) {
 
 TEST_F(BrowserLoaderTest, OnLoadSelectionPolicyIsRootfs) {
   ScopedLacrosSelectionCache cache(
-      browser_util::LacrosSelectionPolicy::kRootfs);
+      ash::standalone_browser::LacrosSelectionPolicy::kRootfs);
   base::test::ScopedCommandLine command_line;
   command_line.GetProcessCommandLine()->AppendSwitchASCII(
-      browser_util::kLacrosSelectionSwitch,
+      ash::standalone_browser::kLacrosSelectionSwitch,
-      browser_util::kLacrosSelectionStateful);
+      ash::standalone_browser::kLacrosSelectionStateful);
 
   // Set stateful lacros version newer than rootfs to test that the selection
   // policy is prioritized higher.
@@ -350,11 +350,11 @@ TEST_F(BrowserLoaderTest, OnLoadSelectionPolicyIsRootfs) {
 TEST_F(BrowserLoaderTest,
        OnLoadSelectionPolicyIsUserChoiceAndCommandLineIsRootfs) {
   ScopedLacrosSelectionCache cache(
-      browser_util::LacrosSelectionPolicy::kUserChoice);
+      ash::standalone_browser::LacrosSelectionPolicy::kUserChoice);
   base::test::ScopedCommandLine command_line;
   command_line.GetProcessCommandLine()->AppendSwitchASCII(
-      browser_util::kLacrosSelectionSwitch,
+      ash::standalone_browser::kLacrosSelectionSwitch,
-      browser_util::kLacrosSelectionRootfs);
+      ash::standalone_browser::kLacrosSelectionRootfs);
 
   // Set stateful lacros version newer than rootfs to test that the user choice
   // is prioritized higher.
@@ -379,11 +379,11 @@ TEST_F(BrowserLoaderTest,
 TEST_F(BrowserLoaderTest,
        OnLoadSelectionPolicyIsUserChoiceAndCommandLineIsStateful) {
   ScopedLacrosSelectionCache cache(
-      browser_util::LacrosSelectionPolicy::kUserChoice);
+      ash::standalone_browser::LacrosSelectionPolicy::kUserChoice);
   base::test::ScopedCommandLine command_line;
   command_line.GetProcessCommandLine()->AppendSwitchASCII(
-      browser_util::kLacrosSelectionSwitch,
+      ash::standalone_browser::kLacrosSelectionSwitch,
-      browser_util::kLacrosSelectionStateful);
+      ash::standalone_browser::kLacrosSelectionStateful);
 
   // Set rootfs lacros version newer than rootfs to test that the user choice
   // is prioritized higher.

chrome/browser/ash/crosapi/browser_manager.cc

@@ -85,6 +85,7 @@
 #include "chrome/common/chrome_paths.h"
 #include "chromeos/ash/components/browser_context_helper/browser_context_helper.h"
 #include "chromeos/ash/components/standalone_browser/browser_support.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "chromeos/ash/components/standalone_browser/migrator_util.h"
 #include "chromeos/crosapi/cpp/crosapi_constants.h"
 #include "chromeos/crosapi/cpp/lacros_startup_state.h"
@@ -1196,7 +1197,8 @@ void BrowserManager::ResumeLaunch() {
   // If Lacros selection (rootfs/stateful) for this user is forced to a
   // different value than the Lacros that was launched at login screen,
   // we need to reload and relaunch the correct version of Lacros.
-  auto user_lacros_selection = browser_util::DetermineLacrosSelection();
+  auto user_lacros_selection =
+      ash::standalone_browser::DetermineLacrosSelection();
   if (user_lacros_selection.has_value() &&
       lacros_selection_ != LacrosSelection::kDeployedLocally &&
       lacros_selection_ != user_lacros_selection) {

chrome/browser/ash/crosapi/browser_manager.h

@@ -31,6 +31,7 @@
 #include "chrome/browser/ash/crosapi/crosapi_id.h"
 #include "chrome/browser/ui/browser_navigator_params.h"
 #include "chromeos/ash/components/dbus/session_manager/session_manager_client.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "chromeos/crosapi/mojom/browser_service.mojom.h"
 #include "chromeos/crosapi/mojom/desk_template.mojom.h"
 #include "components/component_updater/component_updater_service.h"
@@ -91,7 +92,7 @@ class FilesAppLauncher;
 class PersistentForcedExtensionKeepAlive;
 class TestMojoConnectionManager;
 
-using browser_util::LacrosSelection;
+using ash::standalone_browser::LacrosSelection;
 using component_updater::ComponentUpdateService;
 
 // Manages the lifetime of lacros-chrome, and its loading status. Observes the

chrome/browser/ash/crosapi/browser_manager_unittest.cc

@@ -25,6 +25,7 @@
 #include "chromeos/ash/components/standalone_browser/browser_support.h"
 #include "chromeos/ash/components/standalone_browser/feature_refs.h"
 #include "chromeos/ash/components/standalone_browser/lacros_availability.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "chromeos/ash/components/standalone_browser/migrator_util.h"
 #include "chromeos/crosapi/mojom/browser_service.mojom-test-utils.h"
 #include "chromeos/crosapi/mojom/browser_service.mojom.h"
@@ -300,9 +301,10 @@ class BrowserManagerTest : public testing::Test {
     EXPECT_TRUE(browser_util::IsLacrosAllowedToLaunch());
   }
 
-  void ExpectCallingLoad(browser_util::LacrosSelection load_selection =
+  void ExpectCallingLoad(
-                             browser_util::LacrosSelection::kRootfs,
+      ash::standalone_browser::LacrosSelection load_selection =
-                         const std::string& lacros_path = "/run/lacros") {
+          ash::standalone_browser::LacrosSelection::kRootfs,
+      const std::string& lacros_path = "/run/lacros") {
     EXPECT_CALL(*browser_loader_, Load(_))
         .WillOnce([load_selection, lacros_path](
                       BrowserLoader::LoadCompletionCallback callback) {
@@ -402,7 +404,7 @@ TEST_F(BrowserManagerTest, LacrosKeepAliveReloadsWhenUpdateAvailable) {
   std::unique_ptr<BrowserManagerScopedKeepAlive> keep_alive =
       fake_browser_manager_->KeepAlive(BrowserManager::Feature::kTestOnly);
 
-  ExpectCallingLoad(browser_util::LacrosSelection::kStateful,
+  ExpectCallingLoad(ash::standalone_browser::LacrosSelection::kStateful,
                     kSampleLacrosPath);
 
   // On simulated termination, KeepAlive restarts Lacros. Since there is an

chrome/browser/ash/crosapi/browser_util.cc

@@ -78,10 +78,6 @@ std::optional<LacrosAvailability> g_lacros_availability_cache;
 std::optional<LacrosDataBackwardMigrationMode>
     g_lacros_data_backward_migration_mode;
 
-// At session start the value for LacrosSelection logic is applied and the
-// result is stored in this variable which is used after that as a cache.
-std::optional<LacrosSelectionPolicy> g_lacros_selection_cache;
-
 // The rootfs lacros-chrome metadata keys.
 constexpr char kLacrosMetadataContentKey[] = "content";
 constexpr char kLacrosMetadataVersionKey[] = "version";
@@ -100,14 +96,6 @@ constexpr auto kLacrosDataBackwardMigrationModeMap =
          LacrosDataBackwardMigrationMode::kKeepAll},
     });
 
-// The conversion map for LacrosSelection policy data. The values must match
-// the ones from LacrosSelection.yaml.
-constexpr auto kLacrosSelectionPolicyMap =
-    base::MakeFixedFlatMap<std::string_view, LacrosSelectionPolicy>({
-        {"user_choice", LacrosSelectionPolicy::kUserChoice},
-        {"rootfs", LacrosSelectionPolicy::kRootfs},
-    });
-
 // Returns primary user's User instance.
 const user_manager::User* GetPrimaryUser() {
   // TODO(crbug.com/40753373): TaskManagerImplTest is not ready to run with
@@ -238,10 +226,6 @@ const ComponentInfo kLacrosDogfoodStableInfo = {
 
 const Channel kLacrosDefaultChannel = Channel::DEV;
 
-const char kLacrosSelectionSwitch[] = "lacros-selection";
-const char kLacrosSelectionRootfs[] = "rootfs";
-const char kLacrosSelectionStateful[] = "stateful";
-
 const char kLaunchOnLoginPref[] = "lacros.launch_on_login";
 const char kProfileDataBackwardMigrationCompletedForUserPref[] =
     "lacros.profile_data_backward_migration_completed_for_user";
@@ -478,58 +462,6 @@ void CacheLacrosDataBackwardMigrationMode(const policy::PolicyMap& map) {
       value ? value->GetString() : std::string_view());
 }
 
-void CacheLacrosSelection(const policy::PolicyMap& map) {
-  if (g_lacros_selection_cache.has_value()) {
-    // Some browser tests might call this multiple times.
-    LOG(ERROR) << "Trying to cache LacrosSelection and the value was set";
-    return;
-  }
-
-  // Users can set this switch in chrome://flags to disable the effect of the
-  // lacros-selection policy. This should only be allows for googlers.
-  const base::CommandLine* cmdline = base::CommandLine::ForCurrentProcess();
-  if (cmdline->HasSwitch(ash::switches::kLacrosSelectionPolicyIgnore) &&
-      IsGoogleInternal(UserManager::Get()->GetPrimaryUser())) {
-    LOG(WARNING) << "LacrosSelection policy is ignored due to the ignore flag";
-    return;
-  }
-
-  const base::Value* value =
-      map.GetValue(policy::key::kLacrosSelection, base::Value::Type::STRING);
-  g_lacros_selection_cache = ParseLacrosSelectionPolicy(
-      value ? value->GetString() : std::string_view());
-}
-
-LacrosSelectionPolicy GetCachedLacrosSelectionPolicy() {
-  return g_lacros_selection_cache.value_or(LacrosSelectionPolicy::kUserChoice);
-}
-
-std::optional<LacrosSelection> DetermineLacrosSelection() {
-  switch (GetCachedLacrosSelectionPolicy()) {
-    case LacrosSelectionPolicy::kRootfs:
-      return LacrosSelection::kRootfs;
-    case LacrosSelectionPolicy::kUserChoice:
-      break;
-  }
-
-  const base::CommandLine* cmdline = base::CommandLine::ForCurrentProcess();
-
-  if (!cmdline->HasSwitch(browser_util::kLacrosSelectionSwitch)) {
-    return std::nullopt;
-  }
-
-  auto value =
-      cmdline->GetSwitchValueASCII(browser_util::kLacrosSelectionSwitch);
-  if (value == browser_util::kLacrosSelectionRootfs) {
-    return LacrosSelection::kRootfs;
-  }
-  if (value == browser_util::kLacrosSelectionStateful) {
-    return LacrosSelection::kStateful;
-  }
-
-  return std::nullopt;
-}
-
 ComponentInfo GetLacrosComponentInfoForChannel(version_info::Channel channel) {
   // We default to the Dev component for UNKNOWN channels.
   static constexpr auto kChannelToComponentInfoMap =
@@ -547,17 +479,18 @@ ComponentInfo GetLacrosComponentInfo() {
   return GetLacrosComponentInfoForChannel(GetStatefulLacrosChannel());
 }
 
-Channel GetLacrosSelectionUpdateChannel(LacrosSelection selection) {
+Channel GetLacrosSelectionUpdateChannel(
+    ash::standalone_browser::LacrosSelection selection) {
   switch (selection) {
-    case LacrosSelection::kRootfs:
+    case ash::standalone_browser::LacrosSelection::kRootfs:
       // For 'rootfs' Lacros use the same channel as ash/OS. Obtained from
       // the LSB's release track property.
       return chrome::GetChannel();
-    case LacrosSelection::kStateful:
+    case ash::standalone_browser::LacrosSelection::kStateful:
       // For 'stateful' Lacros directly check the channel of stateful-lacros
       // that the user is on.
       return GetStatefulLacrosChannel();
-    case LacrosSelection::kDeployedLocally:
+    case ash::standalone_browser::LacrosSelection::kDeployedLocally:
       // For locally deployed Lacros there is no channel so return unknown.
       return Channel::UNKNOWN;
   }
@@ -607,10 +540,6 @@ void ClearLacrosDataBackwardMigrationModeCacheForTest() {
   g_lacros_data_backward_migration_mode.reset();
 }
 
-void ClearLacrosSelectionCacheForTest() {
-  g_lacros_selection_cache.reset();
-}
-
 std::optional<MigrationStatus> GetMigrationStatus() {
   PrefService* local_state = g_browser_process->local_state();
   if (!local_state) {
@@ -727,16 +656,6 @@ LacrosLaunchSwitchSource GetLacrosLaunchSwitchSource() {
              : LacrosLaunchSwitchSource::kForcedByPolicy;
 }
 
-std::optional<LacrosSelectionPolicy> ParseLacrosSelectionPolicy(
-    std::string_view value) {
-  auto it = kLacrosSelectionPolicyMap.find(value);
-  if (it != kLacrosSelectionPolicyMap.end())
-    return it->second;
-
-  LOG(ERROR) << "Unknown LacrosSelection policy value is passed: " << value;
-  return std::nullopt;
-}
-
 std::optional<LacrosDataBackwardMigrationMode>
 ParseLacrosDataBackwardMigrationMode(std::string_view value) {
   auto it = kLacrosDataBackwardMigrationModeMap.find(value);
@@ -761,17 +680,6 @@ std::string_view GetLacrosDataBackwardMigrationModeName(
   return std::string_view();
 }
 
-std::string_view GetLacrosSelectionPolicyName(LacrosSelectionPolicy value) {
-  for (const auto& entry : kLacrosSelectionPolicyMap) {
-    if (entry.second == value) {
-      return entry.first;
-    }
-  }
-
-  NOTREACHED();
-  return std::string_view();
-}
-
 bool IsAshBrowserSyncEnabled() {
   // Turn off sync from Ash if Lacros is enabled and Ash web browser is
   // disabled.

chrome/browser/ash/crosapi/browser_util.h

@@ -13,6 +13,7 @@
 #include "base/feature_list.h"
 #include "base/time/time.h"
 #include "chromeos/ash/components/standalone_browser/lacros_availability.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 
 class PrefRegistrySimple;
 class PrefService;
@@ -68,29 +69,6 @@ enum class LacrosLaunchSwitchSource {
   kForcedByPolicy = 3
 };
 
-// Represents the policy indicating which Lacros browser to launch, named
-// LacrosSelection. The values shall be consistent with the controlling
-// policy. Unlike `LacrosSelection` representing which lacros to select,
-// `LacrosSelectionPolicy` represents how to decide which lacros to select.
-// Stateful option from `LacrosSelection` is omitted due to a breakage risks in
-// case of version skew (e.g. when the latest stateful Lacros available in omaha
-// is older than the rootfs Lacros on the device).
-enum class LacrosSelectionPolicy {
-  // Indicates that the user decides which Lacros browser to launch: rootfs or
-  // stateful.
-  kUserChoice = 0,
-  // Indicates that rootfs Lacros will always be launched.
-  kRootfs = 1,
-};
-
-// Represents the different options available for lacros selection.
-enum class LacrosSelection {
-  kRootfs = 0,
-  kStateful = 1,
-  kDeployedLocally = 2,
-  kMaxValue = kDeployedLocally,
-};
-
 // Represents the values of the LacrosDataBackwardMigrationMode string enum
 // policy. It controls what happens when we switch from Lacros back to Ash.
 // The values shall be consistent with the policy description.
@@ -147,12 +125,6 @@ extern const char kLacrosStabilityChannelDev[];
 extern const char kLacrosStabilityChannelBeta[];
 extern const char kLacrosStabilityChannelStable[];
 
-// A command-line switch that can also be set from chrome://flags that chooses
-// which selection of Lacros to use.
-extern const char kLacrosSelectionSwitch[];
-extern const char kLacrosSelectionRootfs[];
-extern const char kLacrosSelectionStateful[];
-
 // The internal name in about_flags.cc for the `LacrosDataBackwardMigrationMode`
 // policy.
 inline constexpr const char
@@ -259,20 +231,6 @@ void CacheLacrosAvailability(const policy::PolicyMap& map);
 // LacrosDataBackwardMigrationMode policy.
 void CacheLacrosDataBackwardMigrationMode(const policy::PolicyMap& map);
 
-// To be called at primary user login, to cache the policy value for
-// LacrosSelection policy. The effective value of the policy does not
-// change for the duration of the user session, so cached value shall be
-// checked.
-void CacheLacrosSelection(const policy::PolicyMap& map);
-
-// Returns cached value of LacrosSelection policy. See `CacheLacrosSelection`
-// for details.
-LacrosSelectionPolicy GetCachedLacrosSelectionPolicy();
-
-// Returns lacros selection option according to LarcrosSelectionPolicy and
-// lacros-selection flag. Returns nullopt if there is no preference.
-std::optional<LacrosSelection> DetermineLacrosSelection();
-
 // Returns the lacros ComponentInfo for a given channel.
 ComponentInfo GetLacrosComponentInfoForChannel(version_info::Channel channel);
 
@@ -281,7 +239,7 @@ ComponentInfo GetLacrosComponentInfo();
 
 // Returns the update channel associated with the given loaded lacros selection.
 version_info::Channel GetLacrosSelectionUpdateChannel(
-    LacrosSelection selection);
+    ash::standalone_browser::LacrosSelection selection);
 
 // Returns the currently installed version of lacros-chrome managed by the
 // component updater. Will return an empty / invalid version if no lacros
@@ -308,9 +266,6 @@ void ClearLacrosAvailabilityCacheForTest();
 // Clears the cached value for LacrosDataBackwardMigrationMode.
 void ClearLacrosDataBackwardMigrationModeCacheForTest();
 
-// Clears the cached value for LacrosSelection policy.
-void ClearLacrosSelectionCacheForTest();
-
 // Returns true if profile migraiton is enabled. If profile migration is
 // enabled, the completion of it is required to enable Lacros.
 bool IsProfileMigrationEnabled(const user_manager::User* user,
@@ -370,11 +325,6 @@ LacrosLaunchSwitchSource GetLacrosLaunchSwitchSource();
 void SetLacrosLaunchSwitchSourceForTest(
     ash::standalone_browser::LacrosAvailability test_value);
 
-// Parses the string representation of LacrosSelection policy value into the
-// enum value. Returns nullopt on unknown value.
-std::optional<LacrosSelectionPolicy> ParseLacrosSelectionPolicy(
-    std::string_view value);
-
 // Parses the string representation of LacrosDataBackwardMigrationMode policy
 // value into the enum value. Returns nullopt on unknown value.
 std::optional<LacrosDataBackwardMigrationMode>
@@ -384,10 +334,6 @@ ParseLacrosDataBackwardMigrationMode(std::string_view value);
 std::string_view GetLacrosDataBackwardMigrationModeName(
     LacrosDataBackwardMigrationMode value);
 
-// Returns the LacrosSelection policy value name from the given value. Returned
-// std::string_view is guaranteed to never be invalidated.
-std::string_view GetLacrosSelectionPolicyName(LacrosSelectionPolicy value);
-
 // Stores that "Go to files button" on the migration error screen is clicked.
 void SetGotoFilesClicked(PrefService* local_state,
                          const std::string& user_id_hash);

chrome/browser/ash/crosapi/browser_util_unittest.cc

@@ -24,6 +24,7 @@
 #include "chrome/test/base/testing_browser_process.h"
 #include "chromeos/ash/components/standalone_browser/browser_support.h"
 #include "chromeos/ash/components/standalone_browser/lacros_availability.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "chromeos/ash/components/standalone_browser/migrator_util.h"
 #include "chromeos/ash/components/standalone_browser/standalone_browser_features.h"
 #include "chromeos/crosapi/mojom/crosapi.mojom.h"
@@ -37,7 +38,6 @@
 
 using ash::standalone_browser::LacrosAvailability;
 using crosapi::browser_util::LacrosLaunchSwitchSource;
-using crosapi::browser_util::LacrosSelection;
 using user_manager::User;
 using version_info::Channel;
 
@@ -78,33 +78,6 @@ class ScopedLacrosAvailabilityCache {
   }
 };
 
-// This implementation of RAII for LacrosSelection is to make it easy reset
-// the state between runs.
-class ScopedLacrosSelectionCache {
- public:
-  explicit ScopedLacrosSelectionCache(
-      browser_util::LacrosSelectionPolicy lacros_selection) {
-    SetLacrosSelection(lacros_selection);
-  }
-  ScopedLacrosSelectionCache(const ScopedLacrosSelectionCache&) = delete;
-  ScopedLacrosSelectionCache& operator=(const ScopedLacrosSelectionCache&) =
-      delete;
-  ~ScopedLacrosSelectionCache() {
-    browser_util::ClearLacrosSelectionCacheForTest();
-  }
-
- private:
-  void SetLacrosSelection(
-      browser_util::LacrosSelectionPolicy lacros_selection) {
-    policy::PolicyMap policy;
-    policy.Set(policy::key::kLacrosSelection, policy::POLICY_LEVEL_MANDATORY,
-               policy::POLICY_SCOPE_USER, policy::POLICY_SOURCE_CLOUD,
-               base::Value(GetLacrosSelectionPolicyName(lacros_selection)),
-               /*external_data_fetcher=*/nullptr);
-    browser_util::CacheLacrosSelection(policy);
-  }
-};
-
 }  // namespace
 
 class BrowserUtilTest : public testing::Test {
@@ -551,16 +524,18 @@ TEST_F(BrowserUtilTest, GetRootfsLacrosVersionMayBlockBadJson) {
 TEST_F(BrowserUtilTest, StatefulLacrosSelectionUpdateChannel) {
   // Assert that when no Lacros stability switch is specified, we return the
   // "unknown" channel.
-  ASSERT_EQ(Channel::UNKNOWN, browser_util::GetLacrosSelectionUpdateChannel(
+  ASSERT_EQ(Channel::UNKNOWN,
-                                  LacrosSelection::kStateful));
+            browser_util::GetLacrosSelectionUpdateChannel(
+                ash::standalone_browser::LacrosSelection::kStateful));
 
   // Assert that when a Lacros stability switch is specified, we return the
   // relevant channel name associated to that switch value.
   base::CommandLine* cmdline = base::CommandLine::ForCurrentProcess();
   cmdline->AppendSwitchNative(browser_util::kLacrosStabilitySwitch,
                               browser_util::kLacrosStabilityChannelBeta);
-  ASSERT_EQ(Channel::BETA, browser_util::GetLacrosSelectionUpdateChannel(
+  ASSERT_EQ(Channel::BETA,
-                               LacrosSelection::kStateful));
+            browser_util::GetLacrosSelectionUpdateChannel(
+                ash::standalone_browser::LacrosSelection::kStateful));
   cmdline->RemoveSwitch(browser_util::kLacrosStabilitySwitch);
 }
 
@@ -797,89 +772,6 @@ TEST_F(BrowserUtilTest, LacrosGoogleRolloutOnly) {
       user, browser_util::PolicyInitState::kAfterInit));
 }
 
-TEST_F(BrowserUtilTest, LacrosSelection) {
-  // Neither policy nor command line have any preference on Lacros selection.
-  EXPECT_FALSE(browser_util::DetermineLacrosSelection());
-
-  {
-    // LacrosSelection policy has precedence over command line.
-    ScopedLacrosSelectionCache cache(
-        browser_util::LacrosSelectionPolicy::kRootfs);
-    base::test::ScopedCommandLine cmd_line;
-    cmd_line.GetProcessCommandLine()->AppendSwitchASCII(
-        browser_util::kLacrosSelectionSwitch,
-        browser_util::kLacrosSelectionStateful);
-    EXPECT_EQ(browser_util::DetermineLacrosSelection(),
-              LacrosSelection::kRootfs);
-  }
-
-  {
-    // LacrosSelection allows command line check, but command line is not set.
-    ScopedLacrosSelectionCache cache(
-        browser_util::LacrosSelectionPolicy::kUserChoice);
-    EXPECT_FALSE(browser_util::DetermineLacrosSelection());
-  }
-
-  {
-    // LacrosSelection allows command line check.
-    ScopedLacrosSelectionCache cache(
-        browser_util::LacrosSelectionPolicy::kUserChoice);
-    base::test::ScopedCommandLine cmd_line;
-    cmd_line.GetProcessCommandLine()->AppendSwitchASCII(
-        browser_util::kLacrosSelectionSwitch,
-        browser_util::kLacrosSelectionRootfs);
-    EXPECT_EQ(browser_util::DetermineLacrosSelection(),
-              LacrosSelection::kRootfs);
-  }
-
-  {
-    // LacrosSelection allows command line check.
-    ScopedLacrosSelectionCache cache(
-        browser_util::LacrosSelectionPolicy::kUserChoice);
-    base::test::ScopedCommandLine cmd_line;
-    cmd_line.GetProcessCommandLine()->AppendSwitchASCII(
-        browser_util::kLacrosSelectionSwitch,
-        browser_util::kLacrosSelectionStateful);
-    EXPECT_EQ(browser_util::DetermineLacrosSelection(),
-              LacrosSelection::kStateful);
-  }
-}
-
-// LacrosSelection has no effect on non-googlers.
-TEST_F(BrowserUtilTest, LacrosSelectionPolicyIgnoreNonGoogle) {
-  AddRegularUser("user@random.com");
-
-  base::test::ScopedCommandLine cmd_line;
-  cmd_line.GetProcessCommandLine()->AppendSwitch(
-      ash::switches::kLacrosSelectionPolicyIgnore);
-
-  {
-    ScopedLacrosSelectionCache cache(
-        browser_util::LacrosSelectionPolicy::kRootfs);
-    EXPECT_EQ(browser_util::GetCachedLacrosSelectionPolicy(),
-              browser_util::LacrosSelectionPolicy::kRootfs);
-    EXPECT_EQ(browser_util::DetermineLacrosSelection(),
-              LacrosSelection::kRootfs);
-  }
-}
-
-// LacrosSelection has an effect on googlers.
-TEST_F(BrowserUtilTest, LacrosSelectionPolicyIgnoreGoogleDisableToUserChoice) {
-  AddRegularUser("user@google.com");
-
-  base::test::ScopedCommandLine cmd_line;
-  cmd_line.GetProcessCommandLine()->AppendSwitch(
-      ash::switches::kLacrosSelectionPolicyIgnore);
-
-  {
-    ScopedLacrosSelectionCache cache(
-        browser_util::LacrosSelectionPolicy::kRootfs);
-    EXPECT_EQ(browser_util::GetCachedLacrosSelectionPolicy(),
-              browser_util::LacrosSelectionPolicy::kUserChoice);
-    EXPECT_FALSE(browser_util::DetermineLacrosSelection());
-  }
-}
-
 // Lacros Only flag is hidden in guest sessions
 TEST_F(BrowserUtilTest, HidingLacrosFlagsForAllGuestUsers) {
   const User* user = fake_user_manager_->AddGuestUser();

chrome/browser/ash/crosapi/crosapi_util.cc

@@ -605,17 +605,17 @@ crosapi::mojom::BrowserInitParams::DeviceType ConvertDeviceType(
 }
 
 crosapi::mojom::BrowserInitParams::LacrosSelection GetLacrosSelection(
-    std::optional<browser_util::LacrosSelection> selection) {
+    std::optional<ash::standalone_browser::LacrosSelection> selection) {
   if (!selection.has_value()) {
     return crosapi::mojom::BrowserInitParams::LacrosSelection::kUnspecified;
   }
 
   switch (selection.value()) {
-    case browser_util::LacrosSelection::kRootfs:
+    case ash::standalone_browser::LacrosSelection::kRootfs:
       return crosapi::mojom::BrowserInitParams::LacrosSelection::kRootfs;
-    case browser_util::LacrosSelection::kStateful:
+    case ash::standalone_browser::LacrosSelection::kStateful:
       return crosapi::mojom::BrowserInitParams::LacrosSelection::kStateful;
-    case browser_util::LacrosSelection::kDeployedLocally:
+    case ash::standalone_browser::LacrosSelection::kDeployedLocally:
       return crosapi::mojom::BrowserInitParams::LacrosSelection::kUnspecified;
   }
 }
@@ -736,7 +736,7 @@ InitialBrowserAction::~InitialBrowserAction() = default;
 void InjectBrowserInitParams(
     mojom::BrowserInitParams* params,
     bool is_keep_alive_enabled,
-    std::optional<browser_util::LacrosSelection> lacros_selection) {
+    std::optional<ash::standalone_browser::LacrosSelection> lacros_selection) {
   params->crosapi_version = crosapi::mojom::Crosapi::Version_;
   params->deprecated_ash_metrics_enabled_has_value = true;
   PrefService* local_state = g_browser_process->local_state();
@@ -993,7 +993,7 @@ void InjectBrowserPostLoginParams(BrowserParams* params,
 mojom::BrowserInitParamsPtr GetBrowserInitParams(
     InitialBrowserAction initial_browser_action,
     bool is_keep_alive_enabled,
-    std::optional<browser_util::LacrosSelection> lacros_selection,
+    std::optional<ash::standalone_browser::LacrosSelection> lacros_selection,
     bool include_post_login_params) {
   mojom::BrowserInitParamsPtr params = mojom::BrowserInitParams::New();
   InjectBrowserInitParams(params.get(), is_keep_alive_enabled,
@@ -1016,7 +1016,7 @@ mojom::BrowserPostLoginParamsPtr GetBrowserPostLoginParams(
 base::ScopedFD CreateStartupData(
     InitialBrowserAction initial_browser_action,
     bool is_keep_alive_enabled,
-    std::optional<LacrosSelection> lacros_selection,
+    std::optional<ash::standalone_browser::LacrosSelection> lacros_selection,
     bool include_post_login_params) {
   const auto& data = GetBrowserInitParams(
       std::move(initial_browser_action), is_keep_alive_enabled,

chrome/browser/ash/crosapi/crosapi_util.h

@@ -14,6 +14,7 @@
 #include "base/files/scoped_file.h"
 #include "base/token.h"
 #include "chrome/browser/ash/crosapi/browser_util.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "chromeos/crosapi/mojom/crosapi.mojom.h"
 #include "components/policy/core/common/cloud/cloud_policy_core.h"
 #include "components/policy/core/common/cloud/component_cloud_policy_service.h"
@@ -59,7 +60,7 @@ struct InitialBrowserAction {
 mojom::BrowserInitParamsPtr GetBrowserInitParams(
     InitialBrowserAction initial_browser_action,
     bool is_keep_alive_enabled,
-    std::optional<browser_util::LacrosSelection> lacros_selection,
+    std::optional<ash::standalone_browser::LacrosSelection> lacros_selection,
     bool include_post_login_params = true);
 
 // Creates a memory backed file containing the serialized |params|,
@@ -70,7 +71,7 @@ mojom::BrowserInitParamsPtr GetBrowserInitParams(
 base::ScopedFD CreateStartupData(
     InitialBrowserAction initial_browser_action,
     bool is_keep_alive_enabled,
-    std::optional<browser_util::LacrosSelection> lacros_selection,
+    std::optional<ash::standalone_browser::LacrosSelection> lacros_selection,
     bool include_post_login_params = true);
 
 // Serializes and writes post-login parameters into the given FD.

chrome/browser/ash/policy/handlers/lacros_selection_policy_handler.cc

@@ -34,7 +34,7 @@ void LacrosSelectionPolicyHandler::ApplyPolicySettings(
     prefs->SetInteger(prefs::kLacrosSelection, static_cast<int>(*enum_value));
 }
 
-std::optional<crosapi::browser_util::LacrosSelectionPolicy>
+std::optional<ash::standalone_browser::LacrosSelectionPolicy>
 LacrosSelectionPolicyHandler::GetValue(const PolicyMap& policies,
                                        PolicyErrorMap* errors) {
   const base::Value* value;
@@ -43,7 +43,7 @@ LacrosSelectionPolicyHandler::GetValue(const PolicyMap& policies,
     return std::nullopt;
 
   auto parsed =
-      crosapi::browser_util::ParseLacrosSelectionPolicy(value->GetString());
+      ash::standalone_browser::ParseLacrosSelectionPolicy(value->GetString());
   if (!parsed.has_value() && errors) {
     errors->AddError(policy_name(), IDS_POLICY_INVALID_SELECTION_ERROR,
                      "LacrosSelection value");

chrome/browser/ash/policy/handlers/lacros_selection_policy_handler.h

@@ -8,7 +8,7 @@
 #include <optional>
 
 #include "build/chromeos_buildflags.h"
-#include "chrome/browser/ash/crosapi/browser_util.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "components/policy/core/browser/configuration_policy_handler.h"
 
 class PrefValueMap;
@@ -31,7 +31,7 @@ class LacrosSelectionPolicyHandler : public TypeCheckingPolicyHandler {
                            PrefValueMap* prefs) override;
 
  private:
-  std::optional<crosapi::browser_util::LacrosSelectionPolicy> GetValue(
+  std::optional<ash::standalone_browser::LacrosSelectionPolicy> GetValue(
       const PolicyMap& policies,
       PolicyErrorMap* errors);
 };

chrome/browser/ash/preferences.cc

@@ -60,6 +60,7 @@
 #include "chromeos/ash/components/settings/cros_settings.h"
 #include "chromeos/ash/components/settings/cros_settings_names.h"
 #include "chromeos/ash/components/standalone_browser/lacros_availability.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "chromeos/ash/components/system/statistics_provider.h"
 #include "chromeos/ash/components/timezone/timezone_resolver.h"
 #include "chromeos/components/disks/disks_prefs.h"
@@ -159,7 +160,7 @@ void Preferences::RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterIntegerPref(
       ::prefs::kLacrosSelection,
       static_cast<int>(
-          crosapi::browser_util::LacrosSelectionPolicy::kUserChoice));
+          ash::standalone_browser::LacrosSelectionPolicy::kUserChoice));
   registry->RegisterStringPref(::prefs::kLacrosDataBackwardMigrationMode, "");
   registry->RegisterBooleanPref(prefs::kDeviceSystemWideTracingEnabled, true);
   registry->RegisterBooleanPref(

chrome/browser/profiles/profile_impl.cc

@@ -200,6 +200,7 @@
 #include "chrome/browser/signin/chrome_device_id_helper.h"
 #include "chromeos/ash/components/account_manager/account_manager_factory.h"
 #include "chromeos/ash/components/standalone_browser/browser_support.h"
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
 #include "components/account_manager_core/chromeos/account_manager.h"
 #include "components/session_manager/core/session_manager.h"
 #include "components/user_manager/user.h"
@@ -669,7 +670,7 @@ void ProfileImpl::LoadPrefsForNormalStartup(bool async_prefs) {
         map, IsNewProfile(), IsRegularProfile());
     crosapi::browser_util::CacheLacrosAvailability(map);
     crosapi::browser_util::CacheLacrosDataBackwardMigrationMode(map);
-    crosapi::browser_util::CacheLacrosSelection(map);
+    ash::standalone_browser::CacheLacrosSelection(map);
   }
 #endif
 }
@@ -1185,7 +1186,7 @@ void ProfileImpl::OnPrefsLoaded(CreateMode create_mode, bool success) {
           map, IsNewProfile(), IsRegularProfile());
       crosapi::browser_util::CacheLacrosAvailability(map);
       crosapi::browser_util::CacheLacrosDataBackwardMigrationMode(map);
-      crosapi::browser_util::CacheLacrosSelection(map);
+      ash::standalone_browser::CacheLacrosSelection(map);
     }
 
     ash::UserSessionManager::GetInstance()->RespectLocalePreferenceWrapper(

chromeos/ash/components/standalone_browser/BUILD.gn

@@ -15,6 +15,8 @@ component("standalone_browser") {
     "browser_support.h",
     "lacros_availability.cc",
     "lacros_availability.h",
+    "lacros_selection.cc",
+    "lacros_selection.h",
     "migrator_util.cc",
     "migrator_util.h",
     "standalone_browser_features.cc",
@@ -39,6 +41,7 @@ source_set("unit_tests") {
 
   sources = [
     "lacros_availability_unittest.cc",
+    "lacros_selection_unittest.cc",
     "migrator_util_unittest.cc",
     "test_util_unittest.cc",
   ]
@@ -48,8 +51,12 @@ source_set("unit_tests") {
     ":test_support",
     "//ash/constants:constants",
     "//base/test:test_support",
+    "//components/account_id",
+    "//components/policy:generated",
+    "//components/policy/core/common",
     "//components/prefs:test_support",
     "//components/user_manager:test_support",
+    "//content/test:test_support",
     "//testing/gtest:gtest",
   ]
 }

chromeos/ash/components/standalone_browser/DEPS

@@ -4,6 +4,11 @@ specific_include_rules = {
     "+components/policy/policy_constants.h",
     "+components/user_manager/user.h",
   ],
+  "lacros_selection\.cc": [
+    "+components/policy/core/common/policy_map.h",
+    "+components/policy/policy_constants.h",
+    "+components/user_manager/user_manager.h",
+  ],
   "browser_support\.cc": [
     "+ash/constants/ash_switches.h",
     "+components/user_manager/user.h",
@@ -13,4 +18,13 @@ specific_include_rules = {
   "lacros_availability_unittest\.cc": [
     "+components/user_manager/fake_user_manager.h",
   ],
+  "lacros_selection_unittest\.cc": [
+    "+ash/constants/ash_switches.h",
+    "+components/account_id/account_id.h",
+    "+components/policy/core/common/policy_map.h",
+    "+components/policy/policy_constants.h",
+    "+components/user_manager/fake_user_manager.h",
+    "+components/user_manager/scoped_user_manager.h",
+    "+components/user_manager/user.h",
+  ]
 }

chromeos/ash/components/standalone_browser/lacros_selection.cc

@@ -0,0 +1,115 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
+
+#include "ash/constants/ash_switches.h"
+#include "base/command_line.h"
+#include "base/containers/fixed_flat_map.h"
+#include "base/containers/flat_map.h"
+#include "base/logging.h"
+#include "base/notreached.h"
+#include "chromeos/ash/components/standalone_browser/lacros_availability.h"
+#include "components/policy/core/common/policy_map.h"
+#include "components/policy/policy_constants.h"
+#include "components/user_manager/user_manager.h"
+
+namespace ash::standalone_browser {
+
+namespace {
+
+// At session start the value for LacrosSelection logic is applied and the
+// result is stored in this variable which is used after that as a cache.
+// TODO(crbug.com/336839132): Move cache related methods to a wrapper class
+// instead of global functions + global variables.
+std::optional<LacrosSelectionPolicy> g_lacros_selection_cache;
+
+// The conversion map for LacrosSelection policy data. The values must match
+// the ones from LacrosSelection.yaml.
+constexpr auto kLacrosSelectionPolicyMap =
+    base::MakeFixedFlatMap<std::string_view, LacrosSelectionPolicy>({
+        {"user_choice", LacrosSelectionPolicy::kUserChoice},
+        {"rootfs", LacrosSelectionPolicy::kRootfs},
+    });
+
+}  // namespace
+
+void CacheLacrosSelection(const policy::PolicyMap& map) {
+  if (g_lacros_selection_cache.has_value()) {
+    // Some browser tests might call this multiple times.
+    LOG(ERROR) << "Trying to cache LacrosSelection and the value was set";
+    return;
+  }
+
+  // Users can set this switch in chrome://flags to disable the effect of the
+  // lacros-selection policy. This should only be allows for googlers.
+  const base::CommandLine* cmdline = base::CommandLine::ForCurrentProcess();
+  if (cmdline->HasSwitch(ash::switches::kLacrosSelectionPolicyIgnore) &&
+      IsGoogleInternal(user_manager::UserManager::Get()->GetPrimaryUser())) {
+    LOG(WARNING) << "LacrosSelection policy is ignored due to the ignore flag";
+    return;
+  }
+
+  const base::Value* value =
+      map.GetValue(policy::key::kLacrosSelection, base::Value::Type::STRING);
+  g_lacros_selection_cache = ParseLacrosSelectionPolicy(
+      value ? value->GetString() : std::string_view());
+}
+
+LacrosSelectionPolicy GetCachedLacrosSelectionPolicy() {
+  return g_lacros_selection_cache.value_or(LacrosSelectionPolicy::kUserChoice);
+}
+
+std::optional<LacrosSelection> DetermineLacrosSelection() {
+  switch (GetCachedLacrosSelectionPolicy()) {
+    case LacrosSelectionPolicy::kRootfs:
+      return LacrosSelection::kRootfs;
+    case LacrosSelectionPolicy::kUserChoice:
+      break;
+  }
+
+  const base::CommandLine* cmdline = base::CommandLine::ForCurrentProcess();
+
+  if (!cmdline->HasSwitch(kLacrosSelectionSwitch)) {
+    return std::nullopt;
+  }
+
+  auto value = cmdline->GetSwitchValueASCII(kLacrosSelectionSwitch);
+  if (value == kLacrosSelectionRootfs) {
+    return LacrosSelection::kRootfs;
+  }
+  if (value == kLacrosSelectionStateful) {
+    return LacrosSelection::kStateful;
+  }
+
+  return std::nullopt;
+}
+
+std::optional<LacrosSelectionPolicy> ParseLacrosSelectionPolicy(
+    std::string_view value) {
+  auto it = kLacrosSelectionPolicyMap.find(value);
+  if (it != kLacrosSelectionPolicyMap.end()) {
+    return it->second;
+  }
+
+  LOG(ERROR) << "Unknown LacrosSelection policy value is passed: " << value;
+  return std::nullopt;
+}
+
+std::string_view GetLacrosSelectionPolicyName(LacrosSelectionPolicy value) {
+  for (const auto& entry : kLacrosSelectionPolicyMap) {
+    if (entry.second == value) {
+      return entry.first;
+    }
+  }
+
+  NOTREACHED();
+  return std::string_view();
+}
+
+void ClearLacrosSelectionCacheForTest() {
+  g_lacros_selection_cache.reset();
+}
+
+}  // namespace ash::standalone_browser

chromeos/ash/components/standalone_browser/lacros_selection.h

@@ -0,0 +1,82 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROMEOS_ASH_COMPONENTS_STANDALONE_BROWSER_LACROS_SELECTION_H_
+#define CHROMEOS_ASH_COMPONENTS_STANDALONE_BROWSER_LACROS_SELECTION_H_
+
+#include <optional>
+#include <string_view>
+
+#include "base/component_export.h"
+
+namespace policy {
+class PolicyMap;
+}  // namespace policy
+
+namespace ash::standalone_browser {
+
+// Represents the policy indicating which Lacros browser to launch, named
+// LacrosSelection. The values shall be consistent with the controlling
+// policy. Unlike `LacrosSelection` representing which lacros to select,
+// `LacrosSelectionPolicy` represents how to decide which lacros to select.
+// Stateful option from `LacrosSelection` is omitted due to a breakage risks in
+// case of version skew (e.g. when the latest stateful Lacros available in omaha
+// is older than the rootfs Lacros on the device).
+enum class LacrosSelectionPolicy {
+  // Indicates that the user decides which Lacros browser to launch: rootfs or
+  // stateful.
+  kUserChoice = 0,
+  // Indicates that rootfs Lacros will always be launched.
+  kRootfs = 1,
+};
+
+// Represents the different options available for lacros selection.
+enum class LacrosSelection {
+  kRootfs = 0,
+  kStateful = 1,
+  kDeployedLocally = 2,
+  kMaxValue = kDeployedLocally,
+};
+
+// A command-line switch that can also be set from chrome://flags that chooses
+// which selection of Lacros to use.
+inline constexpr char kLacrosSelectionSwitch[] = "lacros-selection";
+inline constexpr char kLacrosSelectionRootfs[] = "rootfs";
+inline constexpr char kLacrosSelectionStateful[] = "stateful";
+
+// To be called at primary user login, to cache the policy value for
+// LacrosSelection policy. The effective value of the policy does not
+// change for the duration of the user session, so cached value shall be
+// checked.
+COMPONENT_EXPORT(CHROMEOS_ASH_COMPONENTS_STANDALONE_BROWSER)
+void CacheLacrosSelection(const policy::PolicyMap& map);
+
+// Returns cached value of LacrosSelection policy. See `CacheLacrosSelection`
+// for details.
+COMPONENT_EXPORT(CHROMEOS_ASH_COMPONENTS_STANDALONE_BROWSER)
+LacrosSelectionPolicy GetCachedLacrosSelectionPolicy();
+
+// Returns lacros selection option according to LarcrosSelectionPolicy and
+// lacros-selection flag. Returns nullopt if there is no preference.
+COMPONENT_EXPORT(CHROMEOS_ASH_COMPONENTS_STANDALONE_BROWSER)
+std::optional<LacrosSelection> DetermineLacrosSelection();
+
+// Parses the string representation of LacrosSelection policy value into the
+// enum value. Returns nullopt on unknown value.
+COMPONENT_EXPORT(CHROMEOS_ASH_COMPONENTS_STANDALONE_BROWSER)
+std::optional<LacrosSelectionPolicy> ParseLacrosSelectionPolicy(
+    std::string_view value);
+
+// Returns the LacrosSelection policy value name from the given value. Returned
+// std::string_view is guaranteed to never be invalidated.
+COMPONENT_EXPORT(CHROMEOS_ASH_COMPONENTS_STANDALONE_BROWSER)
+std::string_view GetLacrosSelectionPolicyName(LacrosSelectionPolicy value);
+
+// Clears the cached value for LacrosSelection policy.
+COMPONENT_EXPORT(CHROMEOS_ASH_COMPONENTS_STANDALONE_BROWSER)
+void ClearLacrosSelectionCacheForTest();
+
+}  // namespace ash::standalone_browser
+
+#endif  // CHROMEOS_ASH_COMPONENTS_STANDALONE_BROWSER_LACROS_SELECTION_H_

chromeos/ash/components/standalone_browser/lacros_selection_unittest.cc

@@ -0,0 +1,170 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chromeos/ash/components/standalone_browser/lacros_selection.h"
+
+#include <memory>
+#include <optional>
+
+#include "ash/constants/ash_switches.h"
+#include "base/test/scoped_command_line.h"
+#include "base/values.h"
+#include "chromeos/ash/components/standalone_browser/browser_support.h"
+#include "components/account_id/account_id.h"
+#include "components/policy/core/common/policy_map.h"
+#include "components/policy/policy_constants.h"
+#include "components/user_manager/fake_user_manager.h"
+#include "components/user_manager/scoped_user_manager.h"
+#include "components/user_manager/user.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+// This implementation of RAII for LacrosSelection is to make it easy reset
+// the state between runs.
+class ScopedLacrosSelectionCache {
+ public:
+  explicit ScopedLacrosSelectionCache(
+      ash::standalone_browser::LacrosSelectionPolicy lacros_selection) {
+    SetLacrosSelection(lacros_selection);
+  }
+  ScopedLacrosSelectionCache(const ScopedLacrosSelectionCache&) = delete;
+  ScopedLacrosSelectionCache& operator=(const ScopedLacrosSelectionCache&) =
+      delete;
+  ~ScopedLacrosSelectionCache() {
+    ash::standalone_browser::ClearLacrosSelectionCacheForTest();
+  }
+
+ private:
+  void SetLacrosSelection(
+      ash::standalone_browser::LacrosSelectionPolicy lacros_selection) {
+    policy::PolicyMap policy;
+    policy.Set(policy::key::kLacrosSelection, policy::POLICY_LEVEL_MANDATORY,
+               policy::POLICY_SCOPE_USER, policy::POLICY_SOURCE_CLOUD,
+               base::Value(GetLacrosSelectionPolicyName(lacros_selection)),
+               /*external_data_fetcher=*/nullptr);
+    ash::standalone_browser::CacheLacrosSelection(policy);
+  }
+};
+
+class LacrosSelectionTest : public testing::Test {
+ public:
+  LacrosSelectionTest() = default;
+  ~LacrosSelectionTest() override = default;
+
+  void SetUp() override {
+    fake_user_manager_.Reset(std::make_unique<user_manager::FakeUserManager>());
+  }
+
+  void TearDown() override {
+    if (ash::standalone_browser::BrowserSupport::
+            IsInitializedForPrimaryUser()) {
+      ash::standalone_browser::BrowserSupport::Shutdown();
+    }
+    fake_user_manager_.Reset();
+    ash::standalone_browser::BrowserSupport::SetCpuSupportedForTesting(
+        std::nullopt);
+  }
+
+  const user_manager::User* AddRegularUser(const std::string& email) {
+    AccountId account_id = AccountId::FromUserEmail(email);
+    const user_manager::User* user = fake_user_manager_->AddUser(account_id);
+    fake_user_manager_->UserLoggedIn(account_id, user->username_hash(),
+                                     /*browser_restart=*/false,
+                                     /*is_child=*/false);
+    ash::standalone_browser::BrowserSupport::InitializeForPrimaryUser(
+        policy::PolicyMap(), false, false);
+    return user;
+  }
+
+ private:
+  user_manager::TypedScopedUserManager<user_manager::FakeUserManager>
+      fake_user_manager_;
+};
+
+TEST_F(LacrosSelectionTest, LacrosSelection) {
+  // Neither policy nor command line have any preference on Lacros selection.
+  EXPECT_FALSE(ash::standalone_browser::DetermineLacrosSelection());
+
+  {
+    // LacrosSelection policy has precedence over command line.
+    ScopedLacrosSelectionCache cache(
+        ash::standalone_browser::LacrosSelectionPolicy::kRootfs);
+    base::test::ScopedCommandLine cmd_line;
+    cmd_line.GetProcessCommandLine()->AppendSwitchASCII(
+        ash::standalone_browser::kLacrosSelectionSwitch,
+        ash::standalone_browser::kLacrosSelectionStateful);
+    EXPECT_EQ(ash::standalone_browser::DetermineLacrosSelection(),
+              ash::standalone_browser::LacrosSelection::kRootfs);
+  }
+
+  {
+    // LacrosSelection allows command line check, but command line is not set.
+    ScopedLacrosSelectionCache cache(
+        ash::standalone_browser::LacrosSelectionPolicy::kUserChoice);
+    EXPECT_FALSE(ash::standalone_browser::DetermineLacrosSelection());
+  }
+
+  {
+    // LacrosSelection allows command line check.
+    ScopedLacrosSelectionCache cache(
+        ash::standalone_browser::LacrosSelectionPolicy::kUserChoice);
+    base::test::ScopedCommandLine cmd_line;
+    cmd_line.GetProcessCommandLine()->AppendSwitchASCII(
+        ash::standalone_browser::kLacrosSelectionSwitch,
+        ash::standalone_browser::kLacrosSelectionRootfs);
+    EXPECT_EQ(ash::standalone_browser::DetermineLacrosSelection(),
+              ash::standalone_browser::LacrosSelection::kRootfs);
+  }
+
+  {
+    // LacrosSelection allows command line check.
+    ScopedLacrosSelectionCache cache(
+        ash::standalone_browser::LacrosSelectionPolicy::kUserChoice);
+    base::test::ScopedCommandLine cmd_line;
+    cmd_line.GetProcessCommandLine()->AppendSwitchASCII(
+        ash::standalone_browser::kLacrosSelectionSwitch,
+        ash::standalone_browser::kLacrosSelectionStateful);
+    EXPECT_EQ(ash::standalone_browser::DetermineLacrosSelection(),
+              ash::standalone_browser::LacrosSelection::kStateful);
+  }
+}
+
+// LacrosSelection has no effect on non-googlers.
+TEST_F(LacrosSelectionTest, LacrosSelectionPolicyIgnoreNonGoogle) {
+  AddRegularUser("user@random.com");
+
+  base::test::ScopedCommandLine cmd_line;
+  cmd_line.GetProcessCommandLine()->AppendSwitch(
+      ash::switches::kLacrosSelectionPolicyIgnore);
+
+  {
+    ScopedLacrosSelectionCache cache(
+        ash::standalone_browser::LacrosSelectionPolicy::kRootfs);
+    EXPECT_EQ(ash::standalone_browser::GetCachedLacrosSelectionPolicy(),
+              ash::standalone_browser::LacrosSelectionPolicy::kRootfs);
+    EXPECT_EQ(ash::standalone_browser::DetermineLacrosSelection(),
+              ash::standalone_browser::LacrosSelection::kRootfs);
+  }
+}
+
+// LacrosSelection has an effect on googlers.
+TEST_F(LacrosSelectionTest,
+       LacrosSelectionPolicyIgnoreGoogleDisableToUserChoice) {
+  AddRegularUser("user@google.com");
+
+  base::test::ScopedCommandLine cmd_line;
+  cmd_line.GetProcessCommandLine()->AppendSwitch(
+      ash::switches::kLacrosSelectionPolicyIgnore);
+
+  {
+    ScopedLacrosSelectionCache cache(
+        ash::standalone_browser::LacrosSelectionPolicy::kRootfs);
+    EXPECT_EQ(ash::standalone_browser::GetCachedLacrosSelectionPolicy(),
+              ash::standalone_browser::LacrosSelectionPolicy::kUserChoice);
+    EXPECT_FALSE(ash::standalone_browser::DetermineLacrosSelection());
+  }
+}
+
+}  // namespace