cc: Cleanup class/struct forward declarations

cc/resources/ui_resource_bitmap.h

 // Copyright 2013 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 CC_RESOURCES_UI_RESOURCE_BITMAP_H_
 #define CC_RESOURCES_UI_RESOURCE_BITMAP_H_
 
 #include <stdint.h>
 
 #include <memory>
 
 #include "base/memory/ref_counted.h"
 #include "cc/base/cc_export.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkPixelRef.h"
 #include "ui/gfx/geometry/size.h"
 
 class SkBitmap;
 
 namespace cc {
 
-class ETC1PixelRef;
-
 // A bitmap class that contains a ref-counted reference to a SkPixelRef that
 // holds the content of the bitmap (cannot use SkBitmap because of ETC1).
 // Thread-safety (by ways of SkPixelRef) ensures that both main and impl threads
 // can hold references to the bitmap and that asynchronous uploads are allowed.
 class CC_EXPORT UIResourceBitmap {
  public:
   enum UIResourceFormat {
     RGBA8,
     ALPHA_8,
     ETC1
@@ skipping 40 matching lines @@
   ~AutoLockUIResourceBitmap();
   const uint8_t* GetPixels() const;
 
  private:
   const UIResourceBitmap& bitmap_;
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_UI_RESOURCE_BITMAP_H_