Add a full Blimp integration test.

blimp/client/core/compositor/blimp_compositor_manager.h

Index: blimp/client/core/compositor/blimp_compositor_manager.h
diff --git a/blimp/client/core/compositor/blimp_compositor_manager.h b/blimp/client/core/compositor/blimp_compositor_manager.h
index 2d12e0ee5ba0ec1ac1b6504e83229761253faa5c..9893a244594a045a32721e287a389eeeb719a851 100644
--- a/blimp/client/core/compositor/blimp_compositor_manager.h
+++ b/blimp/client/core/compositor/blimp_compositor_manager.h
@@ -37,6 +37,11 @@ class BlimpCompositorManager
 
   bool OnTouchEvent(const ui::MotionEvent& motion_event);
 
+  // Notifies |callback| when all pending commits on the active BlimpCompositor
+  // have been drawn to the screen.  If the active compositor is destroyed or
+  // becomes hidden |callback| will be notified.
+  void NotifyWhenDonePendingCommits(base::Closure callback);
+
   scoped_refptr<cc::Layer> layer() const { return layer_; }
 
  protected: