[4/N] Remove IsOnBatteryPower and replace it with GetBatteryPowerStatus

This CL is part of a series of a CLs to expose the tristate enum
to all consumers, for more context please see https://docs.google.com/document/d/1znskYZJyfhbGmyu7OQC4-A58zdrl9_xyZT7E-jTbyXE/.

This CL removes IsOnBatteryPower from PowerMonitorSource and replaces
it with GetBatteryPowerStatus. It changes all the necassary files to
make that complete.

Bug: 339859756
Change-Id: I76a4b322333f4caacba3069c09ff10b01f025294
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5823390
Reviewed-by: Francois Pierre Doray <fdoray@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: Alex Gough <ajgo@chromium.org>
Commit-Queue: Sayed Elabady <elabadysayed@chromium.org>
Reviewed-by: Arthur Sonzogni <arthursonzogni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1352655}

base/power_monitor/power_monitor_device_source.cc

@@ -8,11 +8,6 @@
 
 namespace base {
 
-bool PowerMonitorDeviceSource::IsOnBatteryPower() const {
-  return GetBatteryPowerStatus() ==
-         PowerStateObserver::BatteryPowerStatus::kBatteryPower;
-}
-
 PowerMonitorDeviceSource::PowerMonitorDeviceSource() {
 #if BUILDFLAG(IS_APPLE) || BUILDFLAG(IS_WIN)
   PlatformInit();

base/power_monitor/power_monitor_device_source.h

@@ -107,17 +107,12 @@ class BASE_EXPORT PowerMonitorDeviceSource : public PowerMonitorSource {
                                        void* message_argument);
 #endif  // BUILDFLAG(IS_MAC)
 
-  // Platform-specific method to check whether the system is currently
-  // running on battery power.  Returns true if running on batteries,
-  // false otherwise.
-  bool IsOnBatteryPower() const final;
-
   // Platform-specific method to check whether the system is currently
   // running on battery power. Returns kBatteryPower if running on battery,
   // kExternalPower if running on external power or kUnknown if the power
   // state is unknown (for example, during early process lifetime when the
   // state hasn't been obtained yet).
-  PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus() const;
+  PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus() const override;
 
 #if BUILDFLAG(IS_ANDROID)
   PowerThermalObserver::DeviceThermalState GetCurrentThermalState()

base/power_monitor/power_monitor_source.h

@@ -45,19 +45,9 @@ class BASE_EXPORT PowerMonitorSource {
   virtual void SetCurrentThermalState(
       PowerThermalObserver::DeviceThermalState state);
 
-  // Platform-specific method to check whether the system is currently
-  // running on battery power.
-  // TODO(339859756): remove this method and make `GetBatteryPowerStatus`
-  // virtual.
-  virtual bool IsOnBatteryPower() const = 0;
-
-  // TOOD(339859756): using `kUnknown` here is temporary and should be cleaned
-  // up once we remove `IsOnBatteryPower`.
-  PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus() const {
-    return IsOnBatteryPower()
-               ? PowerStateObserver::BatteryPowerStatus::kBatteryPower
-               : PowerStateObserver::BatteryPowerStatus::kUnknown;
-  }
+  // Platform-specific method to determine the battery power status.
+  virtual PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus()
+      const = 0;
 
 #if BUILDFLAG(IS_ANDROID)
   // Read and return the current remaining battery capacity (microampere-hours).

base/power_monitor/power_monitor_unittest.cc

@@ -84,10 +84,10 @@ TEST_F(PowerMonitorTest, PowerNotifications) {
 
   // Pretend the device has gone off battery power
   source().GeneratePowerStateEvent(
-      PowerStateObserver::BatteryPowerStatus::kUnknown);
+      PowerStateObserver::BatteryPowerStatus::kExternalPower);
   EXPECT_EQ(observers[0].power_state_changes(), 2);
   EXPECT_EQ(observers[0].last_power_status(),
-            PowerStateObserver::BatteryPowerStatus::kUnknown);
+            PowerStateObserver::BatteryPowerStatus::kExternalPower);
 
   // Repeated indications the device is off battery power should be suppressed.
   source().GeneratePowerStateEvent(

base/test/power_monitor_test.cc

@@ -21,8 +21,7 @@ class PowerMonitorTestSource : public PowerMonitorSource {
   // Retrieve current states.
   PowerThermalObserver::DeviceThermalState GetCurrentThermalState()
       const override;
-  PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus() const;
-  bool IsOnBatteryPower() const override;
+  PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus() const override;
 
   // Sends asynchronous notifications to registered observers.
   void Suspend();
@@ -88,11 +87,6 @@ PowerMonitorTestSource::GetBatteryPowerStatus() const {
   return test_power_status_;
 }
 
-bool PowerMonitorTestSource::IsOnBatteryPower() const {
-  return test_power_status_ ==
-         PowerStateObserver::BatteryPowerStatus::kBatteryPower;
-}
-
 void PowerMonitorTestSource::GenerateThermalThrottlingEvent(
     PowerThermalObserver::DeviceThermalState new_thermal_state) {
   ProcessThermalEvent(new_thermal_state);

chrome/browser/performance_manager/test_support/fake_power_monitor_source.cc

@@ -16,9 +16,5 @@ void FakePowerMonitorSource::SetBatteryPowerStatus(
   battery_power_status_ = battery_power_status;
   ProcessPowerEvent(POWER_STATE_EVENT);
 }
-bool FakePowerMonitorSource::IsOnBatteryPower() const {
-  return GetBatteryPowerStatus() ==
-         base::PowerStateObserver::BatteryPowerStatus::kBatteryPower;
-}
 
 }  // namespace performance_manager

chrome/browser/performance_manager/test_support/fake_power_monitor_source.h

@@ -13,10 +13,10 @@ namespace performance_manager {
 
 class FakePowerMonitorSource : public base::PowerMonitorSource {
  public:
-  base::PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus() const;
+  base::PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus()
+      const override;
   void SetBatteryPowerStatus(
       base::PowerStateObserver::BatteryPowerStatus battery_power_status);
-  bool IsOnBatteryPower() const override;
 
  private:
   base::PowerStateObserver::BatteryPowerStatus battery_power_status_ =

components/download/internal/background_service/scheduler/battery_status_listener.h

@@ -5,6 +5,8 @@
 #ifndef COMPONENTS_DOWNLOAD_INTERNAL_BACKGROUND_SERVICE_SCHEDULER_BATTERY_STATUS_LISTENER_H_
 #define COMPONENTS_DOWNLOAD_INTERNAL_BACKGROUND_SERVICE_SCHEDULER_BATTERY_STATUS_LISTENER_H_
 
+#include "base/power_monitor/power_observer.h"
+
 namespace download {
 
 // Interface to monitor device battery status.
@@ -13,7 +15,8 @@ class BatteryStatusListener {
   class Observer {
    public:
     // Called when device charging state changed.
-    virtual void OnPowerStateChange(bool on_battery_power) = 0;
+    virtual void OnPowerStateChange(
+        base::PowerStateObserver::BatteryPowerStatus battery_power_status) = 0;
 
    protected:
     virtual ~Observer() {}
@@ -24,7 +27,8 @@ class BatteryStatusListener {
   virtual int GetBatteryPercentage() = 0;
 
   // Is the device is using battery power instead of charging.
-  virtual bool IsOnBatteryPower() const = 0;
+  virtual base::PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus()
+      const = 0;
 
   // Start/Stop to listen to battery status changes.
   virtual void Start(Observer* observer) = 0;

components/download/internal/background_service/scheduler/battery_status_listener_impl.cc

@@ -22,9 +22,9 @@ int BatteryStatusListenerImpl::GetBatteryPercentage() {
   return battery_percentage_;
 }
 
-bool BatteryStatusListenerImpl::IsOnBatteryPower() const {
-  return (base::PowerMonitor::GetInstance()->GetBatteryPowerStatus() ==
-          base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
+base::PowerStateObserver::BatteryPowerStatus
+BatteryStatusListenerImpl::GetBatteryPowerStatus() const {
+  return base::PowerMonitor::GetInstance()->GetBatteryPowerStatus();
 }
 
 void BatteryStatusListenerImpl::Start(Observer* observer) {
@@ -60,9 +60,7 @@ void BatteryStatusListenerImpl::UpdateBatteryPercentage(bool force) {
 void BatteryStatusListenerImpl::OnBatteryPowerStatusChange(
     base::PowerStateObserver::BatteryPowerStatus battery_power_status) {
   if (observer_)
-    observer_->OnPowerStateChange(
-        battery_power_status ==
-        base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
+    observer_->OnPowerStateChange(battery_power_status);
 }
 
 }  // namespace download

components/download/internal/background_service/scheduler/battery_status_listener_impl.h

@@ -34,7 +34,8 @@ class BatteryStatusListenerImpl : public BatteryStatusListener,
  private:
   // BatteryStatusListener implementation.
   int GetBatteryPercentage() override;
-  bool IsOnBatteryPower() const override;
+  base::PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus()
+      const override;
   void Start(Observer* observer) override;
   void Stop() override;
 

components/download/internal/background_service/scheduler/battery_status_listener_mac.cc

@@ -14,8 +14,9 @@ int BatteryStatusListenerMac::GetBatteryPercentage() {
   return 100;
 }
 
-bool BatteryStatusListenerMac::IsOnBatteryPower() const {
-  return false;
+base::PowerStateObserver::BatteryPowerStatus
+BatteryStatusListenerMac::GetBatteryPowerStatus() const {
+  return base::PowerStateObserver::BatteryPowerStatus::kUnknown;
 }
 
 void BatteryStatusListenerMac::Start(Observer* observer) {}

components/download/internal/background_service/scheduler/battery_status_listener_mac.h

@@ -25,7 +25,8 @@ class BatteryStatusListenerMac : public BatteryStatusListener {
  private:
   // BatteryStatusListener implementation.
   int GetBatteryPercentage() override;
-  bool IsOnBatteryPower() const override;
+  base::PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus()
+      const override;
   void Start(Observer* observer) override;
   void Stop() override;
 };

components/download/internal/background_service/scheduler/device_status.h

@@ -13,6 +13,7 @@ namespace download {
 enum class BatteryStatus {
   CHARGING = 0,
   NOT_CHARGING = 1,
+  UNKNOWN = 2,
 };
 
 // NetworkStatus should mostly one to one map to

components/download/internal/background_service/scheduler/device_status_listener.cc

@@ -10,10 +10,18 @@ namespace download {
 
 namespace {
 
-// Converts |on_battery_power| to battery status.
-BatteryStatus ToBatteryStatus(bool on_battery_power) {
-  return on_battery_power ? BatteryStatus::NOT_CHARGING
-                          : BatteryStatus::CHARGING;
+// Converts |battery_power_status| to battery status.
+BatteryStatus ToBatteryStatus(
+    base::PowerStateObserver::BatteryPowerStatus battery_power_status) {
+  switch (battery_power_status) {
+    case base::PowerStateObserver::BatteryPowerStatus::kBatteryPower:
+      return BatteryStatus::NOT_CHARGING;
+    case base::PowerStateObserver::BatteryPowerStatus::kExternalPower:
+      // TODO(339859756): We return CHARGING for kUnknown to preserve the old
+      // behavior.
+    case base::PowerStateObserver::BatteryPowerStatus::kUnknown:
+      return BatteryStatus::CHARGING;
+  }
 }
 
 // Converts a ConnectionType to NetworkStatus.
@@ -92,13 +100,13 @@ void DeviceStatusListener::StartAfterDelay() {
   DCHECK(battery_listener_);
   battery_listener_->Start(this);
   status_.battery_status =
-      ToBatteryStatus(battery_listener_->IsOnBatteryPower());
+      ToBatteryStatus(battery_listener_->GetBatteryPowerStatus());
 
   // Listen to network status changes.
   network_listener_->Start(this);
 
   status_.battery_status =
-      ToBatteryStatus(battery_listener_->IsOnBatteryPower());
+      ToBatteryStatus(battery_listener_->GetBatteryPowerStatus());
   status_.network_status =
       ToNetworkStatus(network_listener_->GetConnectionType());
   pending_network_status_ = status_.network_status;
@@ -159,8 +167,9 @@ void DeviceStatusListener::OnNetworkChanged(
   }
 }
 
-void DeviceStatusListener::OnPowerStateChange(bool on_battery_power) {
-  status_.battery_status = ToBatteryStatus(on_battery_power);
+void DeviceStatusListener::OnPowerStateChange(
+    base::PowerStateObserver::BatteryPowerStatus battery_power_status) {
+  status_.battery_status = ToBatteryStatus(battery_power_status);
   NotifyStatusChange();
 }
 

components/download/internal/background_service/scheduler/device_status_listener.h

@@ -75,7 +75,8 @@ class DeviceStatusListener : public NetworkStatusListener::Observer,
   void StartAfterDelay();
 
   // BatteryStatusListener::Observer implementation.
-  void OnPowerStateChange(bool on_battery_power) override;
+  void OnPowerStateChange(base::PowerStateObserver::BatteryPowerStatus
+                              battery_power_status) override;
 
   // Notifies the observer about device status change.
   void NotifyStatusChange();

components/power_monitor/power_monitor_device_source_linux.cc

@@ -47,11 +47,12 @@ PowerMonitorDeviceSourceLinux::~PowerMonitorDeviceSourceLinux() {
     ShutdownBus();
 }
 
-bool PowerMonitorDeviceSourceLinux::IsOnBatteryPower() const {
+base::PowerStateObserver::BatteryPowerStatus
+PowerMonitorDeviceSourceLinux::GetBatteryPowerStatus() const {
   // TODO(crbug.com/40836663): Use org.freedesktop.UPower to check for
   // OnBattery. One possibility is to connect to the DeviceService's
   // BatteryMonitor.
-  return false;
+  return base::PowerStateObserver::BatteryPowerStatus::kUnknown;
 }
 
 void PowerMonitorDeviceSourceLinux::ShutdownBus() {

components/power_monitor/power_monitor_device_source_linux.h

@@ -27,7 +27,8 @@ class PowerMonitorDeviceSourceLinux : public base::PowerMonitorSource {
   ~PowerMonitorDeviceSourceLinux() override;
 
   // base::PowerMonitorSource:
-  bool IsOnBatteryPower() const override;
+  base::PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus()
+      const override;
 
  private:
   void ShutdownBus();

components/viz/service/main/viz_main_impl_unittest.cc

@@ -74,7 +74,10 @@ class MockPowerMonitorSource : public base::PowerMonitorSource {
 
   ~MockPowerMonitorSource() override { *leak_guard_ = false; }
 
-  bool IsOnBatteryPower() const override { return false; }
+  base::PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus()
+      const override {
+    return base::PowerStateObserver::BatteryPowerStatus::kUnknown;
+  }
 
  private:
   // An external flag to signal as to whether or not this object is still

content/browser/power_monitor_browsertest.cc

@@ -6,6 +6,7 @@
 
 #include "base/functional/bind.h"
 #include "base/functional/callback_helpers.h"
+#include "base/power_monitor/power_observer.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
@@ -37,12 +38,15 @@ namespace content {
 
 namespace {
 
-void VerifyPowerStateInChildProcess(mojom::PowerMonitorTest* power_monitor_test,
-                                    bool expected_state) {
+void VerifyPowerStateInChildProcess(
+    mojom::PowerMonitorTest* power_monitor_test,
+    base::PowerStateObserver::BatteryPowerStatus expected_state) {
   base::RunLoop run_loop;
   power_monitor_test->QueryNextState(base::BindOnce(
-      [](base::RunLoop* loop, bool expected_state, bool on_battery_power) {
-        EXPECT_EQ(expected_state, on_battery_power);
+      [](base::RunLoop* loop,
+         base::PowerStateObserver::BatteryPowerStatus expected_state,
+         base::PowerStateObserver::BatteryPowerStatus battery_power_status) {
+        EXPECT_EQ(expected_state, battery_power_status);
         loop->Quit();
       },
       &run_loop, expected_state));
@@ -69,18 +73,20 @@ class MockPowerMonitorMessageBroadcaster : public device::mojom::PowerMonitor {
                      pending_power_monitor_client) override {
     mojo::Remote<device::mojom::PowerMonitorClient> power_monitor_client(
         std::move(pending_power_monitor_client));
-    power_monitor_client->PowerStateChange(on_battery_power_);
+    power_monitor_client->PowerStateChange(battery_power_status_);
     clients_.Add(std::move(power_monitor_client));
   }
 
-  void OnPowerStateChange(bool on_battery_power) {
-    on_battery_power_ = on_battery_power;
+  void OnPowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus battery_power_status) {
+    battery_power_status_ = battery_power_status;
     for (auto& client : clients_)
-      client->PowerStateChange(on_battery_power);
+      client->PowerStateChange(battery_power_status);
   }
 
  private:
-  bool on_battery_power_ = false;
+  base::PowerStateObserver::BatteryPowerStatus battery_power_status_ =
+      base::PowerStateObserver::BatteryPowerStatus::kUnknown;
 
   mojo::ReceiverSet<device::mojom::PowerMonitor> receivers_;
   mojo::RemoteSet<device::mojom::PowerMonitorClient> clients_;
@@ -160,8 +166,9 @@ class PowerMonitorTest : public ContentBrowserTest {
   int request_count_from_utility() { return request_count_from_utility_; }
   int request_count_from_gpu() { return request_count_from_gpu_; }
 
-  void SimulatePowerStateChange(bool on_battery_power) {
-    power_monitor_message_broadcaster_.OnPowerStateChange(on_battery_power);
+  void SimulatePowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus battery_power_status) {
+    power_monitor_message_broadcaster_.OnPowerStateChange(battery_power_status);
   }
 
  private:
@@ -233,13 +240,26 @@ IN_PROC_BROWSER_TEST_F(PowerMonitorTest, TestRendererProcess) {
   // power state change.
   power_monitor_renderer.FlushForTesting();
 
-  SimulatePowerStateChange(true);
-  // Verify renderer process on_battery_power changed to true.
-  VerifyPowerStateInChildProcess(power_monitor_renderer.get(), true);
+  SimulatePowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
+  // Verify renderer process battery_power_status changed to battery power.
+  VerifyPowerStateInChildProcess(
+      power_monitor_renderer.get(),
+      base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
 
-  SimulatePowerStateChange(false);
-  // Verify renderer process on_battery_power changed to false.
-  VerifyPowerStateInChildProcess(power_monitor_renderer.get(), false);
+  SimulatePowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kExternalPower);
+  // Verify renderer process battery_power_status changed to external power.
+  VerifyPowerStateInChildProcess(
+      power_monitor_renderer.get(),
+      base::PowerStateObserver::BatteryPowerStatus::kExternalPower);
+
+  SimulatePowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kUnknown);
+  // Verify renderer process battery_power_status becomes unknown.
+  VerifyPowerStateInChildProcess(
+      power_monitor_renderer.get(),
+      base::PowerStateObserver::BatteryPowerStatus::kUnknown);
 }
 
 IN_PROC_BROWSER_TEST_F(PowerMonitorTest, TestUtilityProcess) {
@@ -256,13 +276,19 @@ IN_PROC_BROWSER_TEST_F(PowerMonitorTest, TestUtilityProcess) {
   // power state change.
   power_monitor_utility.FlushForTesting();
 
-  SimulatePowerStateChange(true);
-  // Verify utility process on_battery_power changed to true.
-  VerifyPowerStateInChildProcess(power_monitor_utility.get(), true);
+  SimulatePowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
+  // Verify renderer process battery_power_status changed to battery power.
+  VerifyPowerStateInChildProcess(
+      power_monitor_utility.get(),
+      base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
 
-  SimulatePowerStateChange(false);
-  // Verify utility process on_battery_power changed to false.
-  VerifyPowerStateInChildProcess(power_monitor_utility.get(), false);
+  SimulatePowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kExternalPower);
+  // Verify renderer process battery_power_status changed to external power.
+  VerifyPowerStateInChildProcess(
+      power_monitor_utility.get(),
+      base::PowerStateObserver::BatteryPowerStatus::kExternalPower);
 }
 
 IN_PROC_BROWSER_TEST_F(PowerMonitorTest, TestGpuProcess) {
@@ -287,13 +313,19 @@ IN_PROC_BROWSER_TEST_F(PowerMonitorTest, TestGpuProcess) {
   // power state change.
   power_monitor_gpu.FlushForTesting();
 
-  SimulatePowerStateChange(true);
-  // Verify gpu process on_battery_power changed to true.
-  VerifyPowerStateInChildProcess(power_monitor_gpu.get(), true);
+  SimulatePowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
+  // Verify gpu process battery_power_status changed to battery power.
+  VerifyPowerStateInChildProcess(
+      power_monitor_gpu.get(),
+      base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
 
-  SimulatePowerStateChange(false);
-  // Verify gpu process on_battery_power changed to false.
-  VerifyPowerStateInChildProcess(power_monitor_gpu.get(), false);
+  SimulatePowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kExternalPower);
+  // Verify gpu process battery_power_status changed to external power.
+  VerifyPowerStateInChildProcess(
+      power_monitor_gpu.get(),
+      base::PowerStateObserver::BatteryPowerStatus::kExternalPower);
 }
 
 }  //  namespace

content/shell/BUILD.gn

@@ -1047,6 +1047,7 @@ mojom("content_browsertests_mojom") {
     "common/render_frame_test_helper.mojom",
   ]
   public_deps = [
+    "//mojo/public/mojom/base",
     "//sandbox/policy/mojom",
     "//third_party/blink/public/mojom/tokens",
   ]

content/shell/common/power_monitor_test.mojom

@@ -3,6 +3,8 @@
 // found in the LICENSE file.
 
 module content.mojom;
+
+import "mojo/public/mojom/base/battery_power_status.mojom";
 import "sandbox/policy/mojom/sandbox.mojom";
 
 // This interface is only for the sake of browser test to query current power
@@ -12,5 +14,6 @@ interface PowerMonitorTest {
   // The power state is reported immediatelly if there is already a change
   // available to notify, otherwise wait until a change happen. Overlapping
   // calls to QueryNextState are prohibited.
-  QueryNextState() => (bool on_battery_power);
+  QueryNextState()
+      => (mojo_base.mojom.BatteryPowerStatus battery_power_status);
 };

content/shell/common/power_monitor_test_impl.cc

@@ -46,9 +46,7 @@ void PowerMonitorTestImpl::OnBatteryPowerStatusChange(
 }
 
 void PowerMonitorTestImpl::ReportState() {
-  std::move(callback_).Run(
-      battery_power_status_ ==
-      base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
+  std::move(callback_).Run(battery_power_status_);
   need_to_report_ = false;
 }
 

mojo/public/cpp/base/BUILD.gn

@@ -56,6 +56,8 @@ component("typemap_traits") {
   output_name = "mojo_base_typemap_traits"
 
   sources = [
+    "battery_power_status_traits.cc",
+    "battery_power_status_traits.h",
     "big_string_mojom_traits.cc",
     "big_string_mojom_traits.h",
     "memory_allocator_dump_cross_process_uid_mojom_traits.cc",

mojo/public/cpp/base/battery_power_status_traits.cc

@@ -0,0 +1,47 @@
+// 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 "mojo/public/cpp/base/battery_power_status_traits.h"
+
+#include "base/notreached.h"
+#include "base/power_monitor/power_observer.h"
+
+namespace mojo {
+
+// static
+mojo_base::mojom::BatteryPowerStatus
+EnumTraits<mojo_base::mojom::BatteryPowerStatus,
+           base::PowerStateObserver::BatteryPowerStatus>::
+    ToMojom(base::PowerStateObserver::BatteryPowerStatus battery_power_status) {
+  switch (battery_power_status) {
+    case base::PowerStateObserver::BatteryPowerStatus::kBatteryPower:
+      return mojo_base::mojom::BatteryPowerStatus::kBatteryPower;
+    case base::PowerStateObserver::BatteryPowerStatus::kExternalPower:
+      return mojo_base::mojom::BatteryPowerStatus::kExternalPower;
+    case base::PowerStateObserver::BatteryPowerStatus::kUnknown:
+      return mojo_base::mojom::BatteryPowerStatus::kUnknown;
+  }
+  NOTREACHED();
+}
+
+// static
+bool EnumTraits<mojo_base::mojom::BatteryPowerStatus,
+                base::PowerStateObserver::BatteryPowerStatus>::
+    FromMojom(mojo_base::mojom::BatteryPowerStatus input,
+              base::PowerStateObserver::BatteryPowerStatus* out) {
+  switch (input) {
+    case mojo_base::mojom::BatteryPowerStatus::kBatteryPower:
+      *out = base::PowerStateObserver::BatteryPowerStatus::kBatteryPower;
+      return true;
+    case mojo_base::mojom::BatteryPowerStatus::kExternalPower:
+      *out = base::PowerStateObserver::BatteryPowerStatus::kExternalPower;
+      return true;
+    case mojo_base::mojom::BatteryPowerStatus::kUnknown:
+      *out = base::PowerStateObserver::BatteryPowerStatus::kUnknown;
+      return true;
+  }
+  return false;
+}
+
+}  // namespace mojo

mojo/public/cpp/base/battery_power_status_traits.h

@@ -0,0 +1,26 @@
+// 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 MOJO_PUBLIC_CPP_BASE_BATTERY_POWER_STATUS_TRAITS_H_
+#define MOJO_PUBLIC_CPP_BASE_BATTERY_POWER_STATUS_TRAITS_H_
+
+#include "base/component_export.h"
+#include "base/power_monitor/power_observer.h"
+#include "mojo/public/mojom/base/battery_power_status.mojom-shared.h"
+
+namespace mojo {
+
+template <>
+struct COMPONENT_EXPORT(MOJO_BASE_TRAITS)
+    EnumTraits<mojo_base::mojom::BatteryPowerStatus,
+               base::PowerStateObserver::BatteryPowerStatus> {
+  static mojo_base::mojom::BatteryPowerStatus ToMojom(
+      base::PowerStateObserver::BatteryPowerStatus battery_power_status);
+  static bool FromMojom(mojo_base::mojom::BatteryPowerStatus input,
+                        base::PowerStateObserver::BatteryPowerStatus* out);
+};
+
+}  // namespace mojo
+
+#endif  // MOJO_PUBLIC_CPP_BASE_BATTERY_POWER_STATUS_TRAITS_H_

mojo/public/mojom/base/BUILD.gn

@@ -12,6 +12,7 @@ mojom_component("base") {
   sources = [
     "absl_status.mojom",
     "application_state.mojom",
+    "battery_power_status.mojom",
     "big_buffer.mojom",
     "big_string.mojom",
     "binder.mojom",
@@ -548,6 +549,20 @@ mojom_component("base") {
         "//mojo/public/cpp/base:typemap_traits",
       ]
     },
+    {
+      types = [
+        {
+          mojom = "mojo_base.mojom.BatteryPowerStatus"
+          cpp = "::base::PowerStateObserver::BatteryPowerStatus"
+        },
+      ]
+      traits_headers =
+          [ "//mojo/public/cpp/base/battery_power_status_traits.h" ]
+      traits_public_deps = [
+        "//base",
+        "//mojo/public/cpp/base:typemap_traits",
+      ]
+    },
   ]
 
   if (is_android) {

mojo/public/mojom/base/battery_power_status.mojom

@@ -0,0 +1,14 @@
+// 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
+
+module mojo_base.mojom;
+
+// Represents the possible states of the battery: running on battery power,
+// charging from an external power source, or an unknown state.
+// This should be in sync with PowerStateObserver::BatteryPowerStatus enum.
+enum BatteryPowerStatus {
+  kUnknown = 0,
+  kBatteryPower = 1,
+  kExternalPower = 2,
+};

services/device/power_monitor/power_monitor_message_broadcaster.cc

@@ -50,10 +50,7 @@ void PowerMonitorMessageBroadcaster::AddClient(
   // new client if battery power status isn't unknown;
   if (battery_power_status_ !=
       base::PowerStateObserver::BatteryPowerStatus::kUnknown) {
-    clients_.Get(element_id)
-        ->PowerStateChange(
-            battery_power_status ==
-            base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
+    clients_.Get(element_id)->PowerStateChange(battery_power_status_);
   }
 }
 
@@ -61,9 +58,7 @@ void PowerMonitorMessageBroadcaster::OnBatteryPowerStatusChange(
     base::PowerStateObserver::BatteryPowerStatus battery_power_status) {
   battery_power_status_ = battery_power_status;
   for (auto& client : clients_)
-    client->PowerStateChange(
-        battery_power_status_ ==
-        base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
+    client->PowerStateChange(battery_power_status_);
 }
 
 void PowerMonitorMessageBroadcaster::OnSuspend() {

services/device/power_monitor/power_monitor_message_broadcaster_unittest.cc

@@ -23,7 +23,8 @@ class MockClient : public PowerMonitorBroadcastSource::Client {
   ~MockClient() override = default;
 
   // Implement device::mojom::PowerMonitorClient
-  void PowerStateChange(bool on_battery_power) override {
+  void PowerStateChange(base::PowerStateObserver::BatteryPowerStatus
+                            battery_power_status) override {
     power_state_changes_++;
     if (service_connected_)
       std::move(service_connected_).Run();

services/device/public/cpp/power_monitor/power_monitor_broadcast_source.cc

@@ -7,8 +7,8 @@
 #include "base/functional/bind.h"
 #include "base/location.h"
 #include "base/task/sequenced_task_runner.h"
+#include "mojo/public/cpp/base/battery_power_status_traits.h"
 #include "mojo/public/cpp/bindings/remote.h"
-
 namespace device {
 
 PowerMonitorBroadcastSource::PowerMonitorBroadcastSource(
@@ -35,8 +35,9 @@ void PowerMonitorBroadcastSource::Init(
   }
 }
 
-bool PowerMonitorBroadcastSource::IsOnBatteryPower() const {
-  return client_->last_reported_on_battery_power_state();
+base::PowerStateObserver::BatteryPowerStatus
+PowerMonitorBroadcastSource::GetBatteryPowerStatus() const {
+  return client_->last_reported_battery_power_status();
 }
 
 PowerMonitorBroadcastSource::Client::Client() = default;
@@ -50,8 +51,8 @@ void PowerMonitorBroadcastSource::Client::Init(
 }
 
 void PowerMonitorBroadcastSource::Client::PowerStateChange(
-    bool on_battery_power) {
-  last_reported_on_battery_power_state_ = on_battery_power;
+    base::PowerStateObserver::BatteryPowerStatus battery_power_status) {
+  last_reported_battery_power_status_ = battery_power_status;
   ProcessPowerEvent(PowerMonitorSource::POWER_STATE_EVENT);
 }
 

services/device/public/cpp/power_monitor/power_monitor_broadcast_source.h

@@ -63,20 +63,23 @@ class PowerMonitorBroadcastSource : public base::PowerMonitorSource {
 
     void Init(mojo::PendingRemote<mojom::PowerMonitor> remote_monitor);
 
-    bool last_reported_on_battery_power_state() const {
-      return last_reported_on_battery_power_state_;
+    base::PowerStateObserver::BatteryPowerStatus
+    last_reported_battery_power_status() const {
+      return last_reported_battery_power_status_;
     }
 
     // device::mojom::PowerMonitorClient implementation
-    // TODO(b/339859756): Change this to broadcast enum instead of boolean.
-    void PowerStateChange(bool on_battery_power) override;
+    void PowerStateChange(base::PowerStateObserver::BatteryPowerStatus
+                              battery_power_status) override;
     void Suspend() override;
     void Resume() override;
 
    private:
     mojo::Receiver<device::mojom::PowerMonitorClient> receiver_{this};
 
-    bool last_reported_on_battery_power_state_ = false;
+    base::PowerStateObserver::BatteryPowerStatus
+        last_reported_battery_power_status_ =
+            base::PowerStateObserver::BatteryPowerStatus::kUnknown;
   };
 
   // This constructor is used by test code to mock the Client class.
@@ -86,7 +89,8 @@ class PowerMonitorBroadcastSource : public base::PowerMonitorSource {
 
   Client* client_for_testing() const { return client_.get(); }
 
-  bool IsOnBatteryPower() const override;
+  base::PowerStateObserver::BatteryPowerStatus GetBatteryPowerStatus()
+      const override;
 
   std::unique_ptr<Client> client_;
   scoped_refptr<base::SequencedTaskRunner> task_runner_;

services/device/public/cpp/power_monitor/power_monitor_broadcast_source_unittest.cc

@@ -82,29 +82,41 @@ TEST_F(PowerMonitorBroadcastSourceTest, PowerMessageReceiveBroadcast) {
   EXPECT_EQ(observer.resumes(), 1);
 
   // Pretend the device has gone on battery power
-  client()->PowerStateChange(true);
+  client()->PowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(observer.power_state_changes(), 1);
   EXPECT_EQ(observer.last_power_status(),
             base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
 
   // Repeated indications the device is on battery power should be suppressed.
-  client()->PowerStateChange(true);
+  client()->PowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kBatteryPower);
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(observer.power_state_changes(), 1);
 
   // Pretend the device has gone off battery power
-  client()->PowerStateChange(false);
+  client()->PowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kExternalPower);
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(observer.power_state_changes(), 2);
   EXPECT_EQ(observer.last_power_status(),
-            base::PowerStateObserver::BatteryPowerStatus::kUnknown);
+            base::PowerStateObserver::BatteryPowerStatus::kExternalPower);
 
   // Repeated indications the device is off battery power should be suppressed.
-  client()->PowerStateChange(false);
+  client()->PowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kExternalPower);
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(observer.power_state_changes(), 2);
 
+  // Sending unknown signal should be propagated properly.
+  client()->PowerStateChange(
+      base::PowerStateObserver::BatteryPowerStatus::kUnknown);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_EQ(observer.power_state_changes(), 3);
+  EXPECT_EQ(observer.last_power_status(),
+            base::PowerStateObserver::BatteryPowerStatus::kUnknown);
+
   power_monitor->RemovePowerSuspendObserver(&observer);
   power_monitor->RemovePowerStateObserver(&observer);
 }

services/device/public/mojom/power_monitor.mojom

@@ -4,15 +4,18 @@
 
 module device.mojom;
 
+import "mojo/public/mojom/base/battery_power_status.mojom";
+
 interface PowerMonitor {
   // Add a client that will be notified on PowerStateChange, Suspend and Resume.
   AddClient(pending_remote<PowerMonitorClient> client);
 };
 
+// Client that broadcasts the battery power status to the current process.
 interface PowerMonitorClient {
   // Notification of a change in power status of the computer, such
-  // as from switching between battery and A/C power.
-  PowerStateChange(bool on_battery_power);
+  // as from switching between battery and A/C power or becoming unknown.
+  PowerStateChange(mojo_base.mojom.BatteryPowerStatus battery_power_status);
 
   // Notification that the system is suspending.
   Suspend();