Add autotestPrivate.bootstrapMachineLearningService

This function makes a basic call using the ML Service client library.
Doing this triggers the ML Service daemon to be started (via D-Bus
service activation) and the D-Bus -> Mojo IPC bootstrap to occur.

The VoidCallback is invoked when the basic call (LoadModel on the test
model) completes successfully.

Tested:
- Ran it with a Chrome OS Tast test (testing successful bootstrap)
- Added a test to the test.js covering the case of failure to connect to
  ML Service

Bug: 836102
Change-Id: I509eab4a518a933109095eec1ece811bc30e4f99
Reviewed-on: https://chromium-review.googlesource.com/1229878
Reviewed-by: Ben Wells <benwells@chromium.org>
Reviewed-by: Achuith Bhandarkar <achuith@chromium.org>
Reviewed-by: Joel Hockey <joelhockey@chromium.org>
Commit-Queue: Andrew Moylan <amoylan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593066}

chrome/browser/extensions/BUILD.gn

@@ -997,6 +997,8 @@ jumbo_static_library("extensions") {
       "//ash/public/cpp",
       "//chromeos/components/proximity_auth",
       "//chromeos/services/ime/public/mojom",
+      "//chromeos/services/machine_learning/public/cpp",
+      "//chromeos/services/machine_learning/public/mojom",
       "//components/arc",
       "//components/chrome_apps",
       "//components/constrained_window",

chrome/browser/extensions/api/autotest_private/autotest_private_api.cc

@@ -5,6 +5,7 @@
 #include "chrome/browser/extensions/api/autotest_private/autotest_private_api.h"
 
 #include <memory>
+#include <sstream>
 #include <utility>
 
 #include "base/lazy_instance.h"
@@ -49,6 +50,7 @@
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/session_manager_client.h"
 #include "chromeos/printing/printer_configuration.h"
+#include "chromeos/services/machine_learning/public/cpp/service_connection.h"
 #include "components/arc/arc_prefs.h"
 #include "components/user_manager/user_manager.h"
 #include "content/public/common/service_manager_connection.h"
@@ -806,6 +808,49 @@ void AutotestPrivateRunCrostiniInstallerFunction::CrostiniRestarted(
 }
 #endif
 
+AutotestPrivateBootstrapMachineLearningServiceFunction::
+    ~AutotestPrivateBootstrapMachineLearningServiceFunction() = default;
+
+AutotestPrivateBootstrapMachineLearningServiceFunction::
+    AutotestPrivateBootstrapMachineLearningServiceFunction() {}
+
+ExtensionFunction::ResponseAction
+AutotestPrivateBootstrapMachineLearningServiceFunction::Run() {
+  DVLOG(1) << "AutotestPrivateBootstrapMachineLearningServiceFunction";
+#if defined(OS_CHROMEOS)
+  // Load a model. This will first bootstrap the Mojo connection to ML Service.
+  chromeos::machine_learning::ServiceConnection::GetInstance()->LoadModel(
+      chromeos::machine_learning::mojom::ModelSpec::New(
+          chromeos::machine_learning::mojom::ModelId::TEST_MODEL),
+      mojo::MakeRequest(&model_),
+      base::BindOnce(
+          &AutotestPrivateBootstrapMachineLearningServiceFunction::ModelLoaded,
+          this));
+  model_.set_connection_error_handler(base::BindOnce(
+      &AutotestPrivateBootstrapMachineLearningServiceFunction::ConnectionError,
+      this));
+  return RespondLater();
+#else
+  return RespondNow(Error(kOnlyAvailableOnChromeOSError));
+#endif
+}
+
+#if defined(OS_CHROMEOS)
+void AutotestPrivateBootstrapMachineLearningServiceFunction::ModelLoaded(
+    chromeos::machine_learning::mojom::LoadModelResult result) {
+  if (result == chromeos::machine_learning::mojom::LoadModelResult::OK) {
+    Respond(NoArguments());
+  } else {
+    Respond(Error(base::StrCat(
+        {"Model load error ", (std::ostringstream() << result).str()})));
+  }
+}
+
+void AutotestPrivateBootstrapMachineLearningServiceFunction::ConnectionError() {
+  Respond(Error("ML Service connection error"));
+}
+#endif
+
 static base::LazyInstance<BrowserContextKeyedAPIFactory<AutotestPrivateAPI>>::
     DestructorAtExit g_autotest_private_api_factory = LAZY_INSTANCE_INITIALIZER;
 

chrome/browser/extensions/api/autotest_private/autotest_private_api.h

@@ -15,6 +15,7 @@
 #if defined(OS_CHROMEOS)
 #include "ash/public/interfaces/ash_message_center_controller.mojom.h"
 #include "chrome/browser/chromeos/printing/cups_printers_manager.h"
+#include "chromeos/services/machine_learning/public/mojom/machine_learning_service.mojom.h"
 #endif
 
 namespace message_center {
@@ -335,6 +336,28 @@ class AutotestPrivateRemovePrinterFunction : public UIThreadExtensionFunction {
   DISALLOW_COPY_AND_ASSIGN(AutotestPrivateRemovePrinterFunction);
 };
 
+class AutotestPrivateBootstrapMachineLearningServiceFunction
+    : public UIThreadExtensionFunction {
+ public:
+  AutotestPrivateBootstrapMachineLearningServiceFunction();
+  DECLARE_EXTENSION_FUNCTION("autotestPrivate.bootstrapMachineLearningService",
+                             AUTOTESTPRIVATE_BOOTSTRAPMACHINELEARNINGSERVICE)
+
+ private:
+  ~AutotestPrivateBootstrapMachineLearningServiceFunction() override;
+  ResponseAction Run() override;
+#if defined(OS_CHROMEOS)
+  // Callbacks for a basic Mojo call to MachineLearningService.LoadModel.
+  void ModelLoaded(chromeos::machine_learning::mojom::LoadModelResult result);
+  void ConnectionError();
+
+  chromeos::machine_learning::mojom::ModelPtr model_;
+#endif
+
+  DISALLOW_COPY_AND_ASSIGN(
+      AutotestPrivateBootstrapMachineLearningServiceFunction);
+};
+
 // Don't kill the browser when we're in a browser test.
 void SetAutotestPrivateTest();
 

chrome/common/extensions/api/autotest_private.idl

@@ -201,5 +201,10 @@ namespace autotestPrivate {
     // |enabled|: Enable Crostini.
     // |callback|: Called when the operation has completed.
     static void setCrostiniEnabled(boolean enabled, VoidCallback callback);
+
+    // Makes a basic request to ML Service, triggering 1. ML Service
+    // daemon startup, and 2. the initial D-Bus -> Mojo IPC bootstrap.
+    // |callback|: Called when the operation has completed.
+    static void bootstrapMachineLearningService(VoidCallback callback);
   };
 };

chrome/test/data/extensions/api_test/autotest_private/test.js

@@ -185,6 +185,10 @@ chrome.test.runTests([
     chrome.autotestPrivate.runCrostiniInstaller(chrome.test.callbackFail(
         'Crostini is not available for the current user'));
   },
+  function bootstrapMachineLearningService() {
+    chrome.autotestPrivate.bootstrapMachineLearningService(
+        chrome.test.callbackFail('ML Service connection error'));
+  },
   function getPrinterList() {
     chrome.autotestPrivate.getPrinterList(function(){
       chrome.test.succeed();

extensions/browser/extension_function_histogram_value.h

@@ -1341,6 +1341,7 @@ enum HistogramValue {
   FILEMANAGERPRIVATEINTERNAL_GETTHUMBNAIL = 1278,
   FILEMANAGERPRIVATEINTERNAL_GETCROSTINISHAREDPATHS = 1279,
   AUTOTESTPRIVATE_LAUNCHAPP = 1280,
+  AUTOTESTPRIVATE_BOOTSTRAPMACHINELEARNINGSERVICE = 1281,
   // Last entry: Add new entries above, then run:
   // python tools/metrics/histograms/update_extension_histograms.py
   ENUM_BOUNDARY

tools/metrics/histograms/enums.xml

@@ -16838,6 +16838,7 @@ Called by update_net_error_codes.py.-->
   <int value="1278" label="FILEMANAGERPRIVATEINTERNAL_GETTHUMBNAIL"/>
   <int value="1279" label="FILEMANAGERPRIVATEINTERNAL_GETCROSTINISHAREDPATHS"/>
   <int value="1280" label="AUTOTESTPRIVATE_LAUNCHAPP"/>
+  <int value="1281" label="AUTOTESTPRIVATE_BOOTSTRAPMACHINELEARNINGSERVICE"/>
 </enum>
 
 <enum name="ExtensionIconState">