Plumb SetVisible from ui::Compositor to the DirectRenderer.

ui/compositor/compositor.h

Index: ui/compositor/compositor.h
diff --git a/ui/compositor/compositor.h b/ui/compositor/compositor.h
index f918f97afdb5dc991da943ceaf53e45c0e8d347e..7546dcf478af7d5032f364f2224543abc5ac0597 100644
--- a/ui/compositor/compositor.h
+++ b/ui/compositor/compositor.h
@@ -139,6 +139,10 @@ class COMPOSITOR_EXPORT ContextFactory {
   // Gets the surface manager.
   virtual cc::SurfaceManager* GetSurfaceManager() = 0;
 
+  // Inform the display corresponding to this compositor if it is visible. When
+  // false it does not need to produce any frames.
+  virtual void SetDisplayVisible(ui::Compositor* compositor, bool visible) = 0;
+
   // Resize the display corresponding to this compositor to a particular size.
   virtual void ResizeDisplay(ui::Compositor* compositor,
                              const gfx::Size& size) = 0;