Adding ArcBridge interface for synchronizing brightness settings

components/arc/power/arc_power_bridge.cc

Index: components/arc/power/arc_power_bridge.cc
diff --git a/components/arc/power/arc_power_bridge.cc b/components/arc/power/arc_power_bridge.cc
index a9a47f52230fa89212c416b9dfca5a0d4cbbd55d..e0b50f84199d084d4ce77d3ab1d181959eab2f03 100644
--- a/components/arc/power/arc_power_bridge.cc
+++ b/components/arc/power/arc_power_bridge.cc
@@ -17,7 +17,7 @@
 namespace arc {
 
 ArcPowerBridge::ArcPowerBridge(ArcBridgeService* bridge_service)
-    : ArcService(bridge_service), binding_(this) {
+    : ArcService(bridge_service), binding_(this), weak_ptr_factory_(this) {
   arc_bridge_service()->power()->AddObserver(this);
 }
 
@@ -34,6 +34,10 @@ void ArcPowerBridge::OnInstanceReady() {
   ash::Shell::GetInstance()->display_configurator()->AddObserver(this);
   chromeos::DBusThreadManager::Get()->GetPowerManagerClient()->
       AddObserver(this);
+  chromeos::DBusThreadManager::Get()
+      ->GetPowerManagerClient()
+      ->GetScreenBrightnessPercent(base::Bind(&ArcPowerBridge::UpdateBrightness,
+                                              weak_ptr_factory_.GetWeakPtr()));
 }
 
 void ArcPowerBridge::OnInstanceClosed() {
@@ -74,6 +78,18 @@ void ArcPowerBridge::OnPowerStateChanged(
   power_instance->SetInteractive(enabled);
 }
 
+void ArcPowerBridge::UpdateBrightness(double percent) {
+  mojom::PowerInstance* power_instance = ARC_GET_INSTANCE_FOR_METHOD(
+      arc_bridge_service()->power(), UpdateBrightness);
+  if (!power_instance)
+    return;
+  power_instance->UpdateBrightness(percent);

[Daniel Erat, 2017/04/05 23:43:38]

nit: just do:

  if (power_instance)
    power_instance->UpdateBrightness(percent);

+}
+
+void ArcPowerBridge::BrightnessChanged(int level, bool user_initiated) {

[Daniel Erat, 2017/04/05 23:43:38]

please make order of methods in .cc files match order in .h

[yueli, 2017/04/06 01:12:37]

Done.

+  UpdateBrightness(static_cast<double>(level));
+}
+
 void ArcPowerBridge::OnAcquireDisplayWakeLock(mojom::DisplayWakeLockType type) {
   if (!chromeos::PowerPolicyController::IsInitialized()) {
     LOG(WARNING) << "PowerPolicyController is not available";
@@ -126,6 +142,13 @@ void ArcPowerBridge::IsDisplayOn(const IsDisplayOnCallback& callback) {
       ash::Shell::GetInstance()->display_configurator()->IsDisplayOn());
 }
 
+void ArcPowerBridge::SetBrightness(double percent) {
+  chromeos::DBusThreadManager::Get()
+      ->GetPowerManagerClient()
+      ->SetScreenBrightnessPercent(percent, true);
+  return;

[Daniel Erat, 2017/04/05 23:43:38]

remove pointless return statement

[yueli, 2017/04/06 01:12:37]

Done.

+}
+
 void ArcPowerBridge::ReleaseAllDisplayWakeLocks() {
   if (!chromeos::PowerPolicyController::IsInitialized()) {
     LOG(WARNING) << "PowerPolicyController is not available";