cc: Cleanup class/struct forward declarations

cc/playback/display_item_list.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 CC_PLAYBACK_DISPLAY_ITEM_LIST_H_
 #define CC_PLAYBACK_DISPLAY_ITEM_LIST_H_
 
 #include <stddef.h>
 
 #include <memory>
 #include <utility>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/trace_event/trace_event.h"
 #include "cc/base/cc_export.h"
 #include "cc/base/contiguous_container.h"
 #include "cc/base/rtree.h"
 #include "cc/playback/discardable_image_map.h"
 #include "cc/playback/display_item.h"
 #include "cc/playback/display_item_list_settings.h"
 #include "third_party/skia/include/core/SkPicture.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 
 class SkCanvas;
-class SkPictureRecorder;
 
 namespace cc {
 class ClientPictureCache;
 class DisplayItem;
-class DrawingDisplayItem;
 
 namespace proto {
 class DisplayItemList;
 }
 
 class CC_EXPORT DisplayItemList
     : public base::RefCountedThreadSafe<DisplayItemList> {
  public:
   // Creates a display item list.
   static scoped_refptr<DisplayItemList> Create(
@@ skipping 177 matching lines @@
   Inputs inputs_;
 
   friend class base::RefCountedThreadSafe<DisplayItemList>;
   FRIEND_TEST_ALL_PREFIXES(DisplayItemListTest, ApproximateMemoryUsage);
   DISALLOW_COPY_AND_ASSIGN(DisplayItemList);
 };
 
 }  // namespace cc
 
 #endif  // CC_PLAYBACK_DISPLAY_ITEM_LIST_H_