cc: Cleanup class/struct forward declarations

cc/trees/draw_property_utils.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_TREES_DRAW_PROPERTY_UTILS_H_
 #define CC_TREES_DRAW_PROPERTY_UTILS_H_
 
 #include "cc/base/cc_export.h"
 #include "cc/layers/layer_collections.h"
 
 namespace gfx {
 class Rect;
 class Transform;
 class Vector2dF;
 }  // namespace gfx
 
 namespace cc {
 
-class ClipTree;
-struct DrawProperties;
 class Layer;
 class LayerImpl;
 class LayerTree;
 class RenderSurfaceImpl;
 class EffectTree;
 class TransformTree;
 class PropertyTrees;
 struct EffectNode;
 
 namespace draw_property_utils {
@@ skipping 102 matching lines @@
 
 void CC_EXPORT
 UpdateElasticOverscroll(PropertyTrees* property_trees,
                         const Layer* overscroll_elasticity_layer,
                         const gfx::Vector2dF& elastic_overscroll);
 
 }  // namespace draw_property_utils
 }  // namespace cc
 
 #endif  // CC_TREES_DRAW_PROPERTY_UTILS_H_