Adding ArcBridge interface for synchronizing brightness settings

components/arc/power/arc_power_bridge.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/arc/power/arc_power_bridge.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "ash/shell.h"
@@ skipping 56 matching lines @@
     chromeos::DisplayPowerState power_state) {
   mojom::PowerInstance* power_instance = ARC_GET_INSTANCE_FOR_METHOD(
       arc_bridge_service()->power(), SetInteractive);
   if (!power_instance)
     return;
 
   bool enabled = (power_state != chromeos::DISPLAY_POWER_ALL_OFF);
   power_instance->SetInteractive(enabled);
 }
 
+void ArcPowerBridge::NotifyBrightnessChange(double percent) {
+  mojom::PowerInstance* power_instance = ARC_GET_INSTANCE_FOR_METHOD(
+      arc_bridge_service()->power(), UpdateBrightness);
+  if (!power_instance)
+    return;
+
+  int brightness = round(percent * 2.55);

[Muyuan, 2017/04/05 18:41:10]

Document why multiply this by 2.55

[yueli, 2017/04/05 19:59:47]

Done.

+  power_instance->UpdateBrightness(brightness);
+}
+
 void ArcPowerBridge::OnAcquireDisplayWakeLock(mojom::DisplayWakeLockType type) {
   if (!chromeos::PowerPolicyController::IsInitialized()) {
     LOG(WARNING) << "PowerPolicyController is not available";
     return;
   }
   chromeos::PowerPolicyController* controller =
       chromeos::PowerPolicyController::Get();
 
   int wake_lock_id = -1;
   switch (type) {
@@ skipping 32 matching lines @@
   }
   controller->RemoveWakeLock(it->second);
   wake_locks_.erase(it);
 }
 
 void ArcPowerBridge::IsDisplayOn(const IsDisplayOnCallback& callback) {
   callback.Run(
       ash::Shell::GetInstance()->display_configurator()->IsDisplayOn());
 }
 
+void ArcPowerBridge::SetBrightness(int32_t brightness) {
+  if (!chromeos::DBusThreadManager::IsInitialized()) {
+    LOG(WARNING) << "DBusThreadManager is not available";
+    return;
+  }
+  chromeos::DBusThreadManager::Get()
+      ->GetPowerManagerClient()
+      ->SetScreenBrightnessPercent(brightness / 2.55, true);
+  return;
+}
+
+void ArcPowerBridge::SyncBrightness() {
+  if (!chromeos::DBusThreadManager::IsInitialized()) {
+    LOG(WARNING) << "DBusThreadManager is not available";
+    return;
+  }
+  chromeos::DBusThreadManager::Get()
+      ->GetPowerManagerClient()
+      ->SyncScreenBrightness();
+  return;
+}
+
 void ArcPowerBridge::ReleaseAllDisplayWakeLocks() {
   if (!chromeos::PowerPolicyController::IsInitialized()) {
     LOG(WARNING) << "PowerPolicyController is not available";
     return;
   }
   chromeos::PowerPolicyController* controller =
       chromeos::PowerPolicyController::Get();
 
   for (const auto& it : wake_locks_) {
     controller->RemoveWakeLock(it.second);
   }
   wake_locks_.clear();
 }
 
 }  // namespace arc