cc: Damage layer on delegated scroll

cc/layers/layer_impl.h

 // Copyright 2011 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_LAYER_IMPL_H_
 #define CC_LAYERS_LAYER_IMPL_H_
 
 #include <set>
 #include <string>
 
@@ skipping 358 matching lines @@
   gfx::Vector2dF bounds_delta() const { return bounds_delta_; }
 
   void SetContentBounds(const gfx::Size& content_bounds);
   gfx::Size content_bounds() const { return draw_properties_.content_bounds; }
 
   float contents_scale_x() const { return draw_properties_.contents_scale_x; }
   float contents_scale_y() const { return draw_properties_.contents_scale_y; }
   void SetContentsScale(float contents_scale_x, float contents_scale_y);
 
   void SetScrollOffsetDelegate(ScrollOffsetDelegate* scroll_offset_delegate);
+  void OnDelegatedScrollOffsetChanged();
   bool IsExternalFlingActive() const;
 
   void SetScrollOffset(const gfx::ScrollOffset& scroll_offset);
   void SetScrollOffsetAndDelta(const gfx::ScrollOffset& scroll_offset,
                                const gfx::Vector2dF& scroll_delta);
   gfx::ScrollOffset scroll_offset() const { return scroll_offset_; }
 
   gfx::ScrollOffset MaxScrollOffset() const;
   gfx::Vector2dF ClampScrollToMaxScrollOffset();
   void SetScrollbarPosition(ScrollbarLayerImplBase* scrollbar_layer,
@@ skipping 318 matching lines @@
   DrawProperties<LayerImpl> draw_properties_;
 
   scoped_refptr<base::debug::ConvertableToTraceFormat> debug_info_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_LAYER_IMPL_H_