Make [S,G]getBacklightsForcedOff dbus API integrated to power_manager_client

chromeos/dbus/power_manager_client.h

Index: chromeos/dbus/power_manager_client.h
diff --git a/chromeos/dbus/power_manager_client.h b/chromeos/dbus/power_manager_client.h
index f4d9ada08d8b5fb6714813ed77dd2727f973716c..9f341deb67370d0e6b51d309357591d960abb5e2 100644
--- a/chromeos/dbus/power_manager_client.h
+++ b/chromeos/dbus/power_manager_client.h
@@ -27,6 +27,9 @@ namespace chromeos {
 // range [0.0, 100.0].
 typedef base::Callback<void(double)> GetScreenBrightnessPercentCallback;
 
+// Callback used for getting the current backlights forced off state.
+typedef base::Callback<void(bool)> GetBacklightsForcedOffCallback;
+
 // PowerManagerClient is used to communicate with the power manager.
 class CHROMEOS_EXPORT PowerManagerClient : public DBusClient {
  public:
@@ -184,6 +187,13 @@ class CHROMEOS_EXPORT PowerManagerClient : public DBusClient {
   // causes powerd to switch to using the battery on devices with type-C ports.
   virtual void SetPowerSource(const std::string& id) = 0;
 
+  // Forces the display and keyboard backlights (if present) to |forced_off|.
+  virtual void SetBacklightsForcedOff(bool forced_off) = 0;
+
+  // Gets the display and keyboard backlights (if present) forced off state.
+  virtual void GetBacklightsForcedOff(
+      const GetBacklightsForcedOffCallback& callback) = 0;
+
   // Returns a callback that can be called by an observer to report
   // readiness for suspend.  See Observer::SuspendImminent().
   virtual base::Closure GetSuspendReadinessCallback() = 0;