chromeos: Add DisplayPowerServiceProvider.

chromeos/display/output_configurator.h

Index: chromeos/display/output_configurator.h
diff --git a/chromeos/display/output_configurator.h b/chromeos/display/output_configurator.h
index ea96a3b41b8dcb96e38112f211df564b3ffe9805..0864feb493c5bf09e3f3e345a3281ea621b0c9ba 100644
--- a/chromeos/display/output_configurator.h
+++ b/chromeos/display/output_configurator.h
@@ -14,6 +14,7 @@
 #include "base/message_loop.h"
 #include "base/timer.h"
 #include "chromeos/chromeos_export.h"
+#include "third_party/cros_system_api/dbus/service_constants.h"
 
 // Forward declarations for Xlib and Xrandr.
 // This is so unused X definitions don't pollute the namespace.
@@ -82,7 +83,7 @@ class CHROMEOS_EXPORT OutputConfigurator : public MessageLoop::Dispatcher {
   // Called when powerd notifies us that some set of displays should be turned
   // on or off.  This requires enabling or disabling the CRTC associated with
   // the display(s) in question so that the low power state is engaged.
-  bool ScreenPowerSet(bool power_on, bool all_displays);
+  bool SetDisplayPowerState(DisplayPowerState state);
 
   // Force switching the display mode to |new_state|.  This method is used when
   // the user explicitly changes the display mode in the options UI.  Returns