content: Cleanup class/struct forward declarations

content/browser/compositor/image_transport_factory.h

 // Copyright 2014 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_BROWSER_COMPOSITOR_IMAGE_TRANSPORT_FACTORY_H_
 #define CONTENT_BROWSER_COMPOSITOR_IMAGE_TRANSPORT_FACTORY_H_
 
 #include <memory>
 #include <string>
 
 #include "base/memory/ref_counted.h"
 #include "build/build_config.h"
 #include "cc/surfaces/surface_id_allocator.h"
 #include "content/common/content_export.h"
 #include "gpu/ipc/common/surface_handle.h"
 #include "ui/events/latency_info.h"
 #include "ui/gfx/native_widget_types.h"
 
 namespace cc {
 class SurfaceManager;
 }
 
 namespace gfx {
-class Size;
 enum class SwapResult;
 }
 
 namespace ui {
 class Compositor;
 class ContextFactory;
-class ContextFactoryObserver;
-class Texture;
 }
 
 namespace display_compositor {
 class GLHelper;
 }
 
 namespace gpu {
 class GpuChannelEstablishFactory;
 }
 
@@ skipping 42 matching lines @@
   // completed. This ensures that content and frames intended for the old
   // NSView will not flash in the new NSView.
   virtual void SetCompositorSuspendedForRecycle(ui::Compositor* compositor,
                                                 bool suspended) = 0;
 #endif
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_COMPOSITOR_IMAGE_TRANSPORT_FACTORY_H_