Implement SkImageFilter support in the compositor.

cc/layer.h

Index: cc/layer.h
diff --git a/cc/layer.h b/cc/layer.h
index e912afb1117bf9a574fb57294004a1bb81c39cc8..6607b3598f72cc8f7ce8b7d28b88bdbca69ce0dc 100644
--- a/cc/layer.h
+++ b/cc/layer.h
@@ -22,6 +22,8 @@ class WebAnimationDelegate;
 class WebLayerScrollClient;
 }
 
+class SkImageFilter;
+
 namespace cc {
 
 class ActiveAnimation;
@@ -95,6 +97,9 @@ public:
     void setFilters(const WebKit::WebFilterOperations&);
     const WebKit::WebFilterOperations& filters() const { return m_filters; }
 
+    void setFilter(SkImageFilter* filter);
+    SkImageFilter* filter() const { return m_filter; }
+
     // Background filters are filters applied to what is behind this layer, when they are viewed through non-opaque
     // regions in this layer. They are used through the WebLayer interface, and are not exposed to HTML.
     void setBackgroundFilters(const WebKit::WebFilterOperations&);
@@ -335,6 +340,7 @@ private:
     float m_debugBorderWidth;
     std::string m_debugName;
     float m_opacity;
+    SkImageFilter* m_filter;
     WebKit::WebFilterOperations m_filters;
     WebKit::WebFilterOperations m_backgroundFilters;
     float m_anchorPointZ;