Mac overlays: Move CALayerPartialDamageTree to its own file

content/common/gpu/image_transport_surface_overlay_mac.h

 // Copyright 2015 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 CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_OVERLAY_MAC_H_
 #define CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_OVERLAY_MAC_H_
 
 #include <list>
 #include <vector>
 
-#include "base/memory/linked_ptr.h"
 #import "base/mac/scoped_nsobject.h"
 #include "base/timer/timer.h"
 #include "content/common/gpu/gpu_command_buffer_stub.h"
 #include "content/common/gpu/image_transport_surface.h"
 #include "ui/gl/gl_surface.h"
 #include "ui/gl/gpu_switching_observer.h"
 
 @class CAContext;
 @class CALayer;
 
@@ skipping 118 matching lines @@
   base::TimeTicks vsync_timebase_;
   base::TimeDelta vsync_interval_;
 
   base::Timer display_pending_swap_timer_;
   base::WeakPtrFactory<ImageTransportSurfaceOverlayMac> weak_factory_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_OVERLAY_MAC_H_