cc: Support anti-aliasing for solid color layers.

cc/shader.h

Index: cc/shader.h
diff --git a/cc/shader.h b/cc/shader.h
index 0d929f90f19af9a1fa20f191abee6468a66f8880..434ea748af75efbd26d636d513a5d5f4d3a48df5 100644
--- a/cc/shader.h
+++ b/cc/shader.h
@@ -328,12 +328,27 @@ public:
     std::string getShaderString() const;
 
     void init(WebKit::WebGraphicsContext3D*, unsigned program, bool usingBindUniform, int* baseUniformIndex);
+    int edgeLocation() const { return -1; }
     int colorLocation() const { return m_colorLocation; }
 
 private:
     int m_colorLocation;
 };
 
+class FragmentShaderColorAA {
+public:
+    FragmentShaderColorAA();
+    std::string getShaderString() const;
+
+    void init(WebKit::WebGraphicsContext3D*, unsigned program, bool usingBindUniform, int* baseUniformIndex);
+    int edgeLocation() const { return m_edgeLocation; }
+    int colorLocation() const { return m_colorLocation; }
+
+private:
+    int m_edgeLocation;
+    int m_colorLocation;
+};
+
 class FragmentShaderCheckerboard {
 public:
     FragmentShaderCheckerboard();