Remove CSSCompositing

sky/engine/core/html/canvas/Canvas2DContextAttributes.h

Index: sky/engine/core/html/canvas/Canvas2DContextAttributes.h
diff --git a/sky/engine/core/html/canvas/Canvas2DContextAttributes.h b/sky/engine/core/html/canvas/Canvas2DContextAttributes.h
index 3dda2451f90c71b3086fa1aeffb4a43b22398892..8a634cd2e04b0d4bbf02e7acfde638f0027d65cb 100644
--- a/sky/engine/core/html/canvas/Canvas2DContextAttributes.h
+++ b/sky/engine/core/html/canvas/Canvas2DContextAttributes.h
@@ -46,10 +46,6 @@ public:
     // Create a new attributes object
     static PassRefPtr<Canvas2DContextAttributes> create();
 
-    // Whether or not the drawing buffer has an alpha channel; default=true
-    bool alpha() const;
-    void setAlpha(bool);
-
     String storage() const;
     void setStorage(const String&);
     Canvas2DContextStorage parsedStorage() const;
@@ -57,7 +53,6 @@ public:
 protected:
     Canvas2DContextAttributes();
 
-    bool m_alpha;
     Canvas2DContextStorage m_storage;
 };