remove unneeded SkShader::validContext

include/core/SkColorShader.h

Index: include/core/SkColorShader.h
diff --git a/include/core/SkColorShader.h b/include/core/SkColorShader.h
index f993959715efa581e0b6b9e92e67679ea752aff6..be59627bc6517b6efda0884ac6264bd0a5accd18 100644
--- a/include/core/SkColorShader.h
+++ b/include/core/SkColorShader.h
@@ -27,8 +27,6 @@ public:
 
     virtual bool isOpaque() const SK_OVERRIDE;
 
-    virtual SkShader::Context* createContext(const ContextRec&, void* storage) const SK_OVERRIDE;
-
     virtual size_t contextSize() const SK_OVERRIDE {
         return sizeof(ColorShaderContext);
     }
@@ -64,6 +62,7 @@ public:
 protected:
     SkColorShader(SkReadBuffer&);
     virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
+    virtual Context* onCreateContext(const ContextRec&, void* storage) const SK_OVERRIDE;
 
 private:
     SkColor     fColor;         // ignored if fInheritColor is true