factories should return baseclass, allowing the impl to specialize

include/effects/SkRectShaderImageFilter.h

Index: include/effects/SkRectShaderImageFilter.h
diff --git a/include/effects/SkRectShaderImageFilter.h b/include/effects/SkRectShaderImageFilter.h
index d78162876fa213b4eaee21be33fdead82d8b2335..9798af2d647fc6544236d2b81b41891f683413ed 100644
--- a/include/effects/SkRectShaderImageFilter.h
+++ b/include/effects/SkRectShaderImageFilter.h
@@ -26,23 +26,24 @@ public:
      *               primitive's bounds are used instead.
      */
     SK_ATTR_DEPRECATED("use Create(SkShader*, const CropRect*)")
-    static SkRectShaderImageFilter* Create(SkShader* s, const SkRect& rect);
+    static SkImageFilter* Create(SkShader* s, const SkRect& rect);
+    static SkImageFilter* Create(SkShader* s, const CropRect* rect = NULL);
 
-    static SkRectShaderImageFilter* Create(SkShader* s, const CropRect* rect = NULL);
-    virtual ~SkRectShaderImageFilter();
     bool affectsTransparentBlack() const override;
 
     SK_TO_STRING_OVERRIDE()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkRectShaderImageFilter)
 
 protected:
-    void flatten(SkWriteBuffer&) const override;
+    virtual ~SkRectShaderImageFilter();
 
-    virtual bool onFilterImage(Proxy*, const SkBitmap& src, const Context&,
-                               SkBitmap* result, SkIPoint* loc) const override;
+    void flatten(SkWriteBuffer&) const override;
+    bool onFilterImage(Proxy*, const SkBitmap& src, const Context&, SkBitmap* result,
+                       SkIPoint* loc) const override;
 
 private:
     SkRectShaderImageFilter(SkShader* s, const CropRect* rect);
+
     SkShader*  fShader;
 
     typedef SkImageFilter INHERITED;