[Athena] Add status icons and system time to the desktop background

athena/screen/public/screen_manager.h

Index: athena/screen/public/screen_manager.h
diff --git a/athena/screen/public/screen_manager.h b/athena/screen/public/screen_manager.h
index 64f90357dee428fdb904288691e57a45ec8b1335..b719b5cf01ede658ac11953a27413ea5bafa7067 100644
--- a/athena/screen/public/screen_manager.h
+++ b/athena/screen/public/screen_manager.h
@@ -14,10 +14,6 @@ namespace aura {
 class Window;
 }
 
-namespace gfx {
-class ImageSkia;
-}
-
 namespace ui {
 class LayerAnimator;
 }
@@ -66,9 +62,6 @@ class ATHENA_EXPORT ScreenManager {
   // Return the context object to be used for widget creation.
   virtual aura::Window* GetContext() = 0;
 
-  // Sets the background image.
-  virtual void SetBackgroundImage(const gfx::ImageSkia& image) = 0;
-
   // Set screen rotation.
   // TODO(flackr): Extract and use ash DisplayManager to set rotation
   // instead: http://crbug.com/401044.