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

chromeos/dbus/fake_power_manager_client.h

Index: chromeos/dbus/fake_power_manager_client.h
diff --git a/chromeos/dbus/fake_power_manager_client.h b/chromeos/dbus/fake_power_manager_client.h
index fc6bbae2f83b546040ed6a7c47dfab38448f01a2..14eca3c39f24a4cfdc98b04f93cec35884435fad 100644
--- a/chromeos/dbus/fake_power_manager_client.h
+++ b/chromeos/dbus/fake_power_manager_client.h
@@ -63,6 +63,9 @@ class CHROMEOS_EXPORT FakePowerManagerClient : public PowerManagerClient {
   void SetPolicy(const power_manager::PowerManagementPolicy& policy) override;
   void SetIsProjecting(bool is_projecting) override;
   void SetPowerSource(const std::string& id) override;
+  void SetBacklightsForcedOff(bool forced_off) override;
+  void GetBacklightsForcedOff(
+      const GetBacklightsForcedOffCallback& callback) override;
   base::Closure GetSuspendReadinessCallback() override;
   int GetNumPendingSuspendReadinessCallbacks() override;
 
@@ -111,6 +114,10 @@ class CHROMEOS_EXPORT FakePowerManagerClient : public PowerManagerClient {
   // Last projecting state set in SetIsProjecting().
   bool is_projecting_;
 
+  // Display and keyboard backlights (if present) forced off state set in
+  // SetBacklightsForcedOff().
+  bool backlights_forced_off_;
+
   // Video activity reports that we were requested to send, in the order they
   // were requested. True if fullscreen.
   std::deque<bool> video_activity_reports_;