Remove remaining use of the deprecated MessageLoopProxy

ui/compositor/compositor.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_COMPOSITOR_COMPOSITOR_H_
 #define UI_COMPOSITOR_COMPOSITOR_H_
 
 #include <list>
 #include <string>
 
@@ skipping 11 matching lines @@
 #include "ui/compositor/compositor_animation_observer.h"
 #include "ui/compositor/compositor_export.h"
 #include "ui/compositor/compositor_observer.h"
 #include "ui/compositor/layer_animator_collection.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/geometry/vector2d.h"
 #include "ui/gfx/gpu_memory_buffer.h"
 #include "ui/gfx/native_widget_types.h"
 
 namespace base {
-class MessageLoopProxy;
 class RunLoop;
+class SingleThreadTaskRunner;
 }
 
 namespace cc {
 class ContextProvider;
 class Layer;
 class LayerTreeDebugState;
 class LayerTreeHost;
 class RendererSettings;
 class SharedBitmapManager;
 class SurfaceIdAllocator;
@@ skipping 323 matching lines @@
   cc::BeginFrameArgs missed_begin_frame_args_;
 
   base::WeakPtrFactory<Compositor> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Compositor);
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_COMPOSITOR_H_