cc: Cleanup class/struct forward declarations

cc/layers/heads_up_display_layer_impl.h

 // Copyright 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 CC_LAYERS_HEADS_UP_DISPLAY_LAYER_IMPL_H_
 #define CC_LAYERS_HEADS_UP_DISPLAY_LAYER_IMPL_H_
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/time/time.h"
 #include "cc/base/cc_export.h"
 #include "cc/debug/debug_rect_history.h"
 #include "cc/layers/layer_impl.h"
 #include "cc/resources/memory_history.h"
 #include "cc/resources/scoped_resource.h"
 #include "third_party/skia/include/core/SkRefCnt.h"
 
 class SkCanvas;
 class SkPaint;
 class SkTypeface;
 struct SkRect;
 
 namespace cc {
 
 class FrameRateCounter;
-class PaintTimeCounter;
 
 class CC_EXPORT HeadsUpDisplayLayerImpl : public LayerImpl {
  public:
   static std::unique_ptr<HeadsUpDisplayLayerImpl> Create(
       LayerTreeImpl* tree_impl,
       int id) {
     return base::WrapUnique(new HeadsUpDisplayLayerImpl(tree_impl, id));
   }
   ~HeadsUpDisplayLayerImpl() override;
 
@@ skipping 106 matching lines @@
   std::vector<DebugRect> paint_rects_;
 
   base::TimeTicks time_of_last_graph_update_;
 
   DISALLOW_COPY_AND_ASSIGN(HeadsUpDisplayLayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_HEADS_UP_DISPLAY_LAYER_IMPL_H_