Change ui::wm::Shadow to use cc::NinePatchLayer.

ui/compositor/layer.h

Index: ui/compositor/layer.h
diff --git a/ui/compositor/layer.h b/ui/compositor/layer.h
index 03041edb872c1f4f66cec65a457f3ebf5aecd4ba..3106894ec95cc34dbb959cb0a1c531cb0661d0d3 100644
--- a/ui/compositor/layer.h
+++ b/ui/compositor/layer.h
@@ -36,6 +36,7 @@ class CopyOutputRequest;
 class DelegatedFrameProvider;
 class DelegatedRendererLayer;
 class Layer;
+class NinePatchLayer;
 class ResourceUpdateQueue;
 class SolidColorLayer;
 class TextureLayer;
@@ -273,6 +274,12 @@ class COMPOSITOR_EXPORT Layer
 
   void SetShowPaintedContent();
 
+  void SetShowNinePatch();
+
+  void UpdateNinePatchBitmap(const SkBitmap& bitmap,
+                             const gfx::Rect& aperture,
+                             const gfx::Rect& border);
+
   // Sets the layer's fill color.  May only be called for LAYER_SOLID_COLOR.
   void SetColor(SkColor color);
 
@@ -469,6 +476,7 @@ class COMPOSITOR_EXPORT Layer
   // Ownership of the layer is held through one of the strongly typed layer
   // pointers, depending on which sort of layer this is.
   scoped_refptr<cc::Layer> content_layer_;
+  scoped_refptr<cc::NinePatchLayer> nine_patch_layer_;
   scoped_refptr<cc::TextureLayer> texture_layer_;
   scoped_refptr<cc::SolidColorLayer> solid_color_layer_;
   scoped_refptr<cc::DelegatedRendererLayer> delegated_renderer_layer_;