factories should return baseclass, allowing the impl to specialize

include/effects/SkOffsetImageFilter.h

 /*
  * Copyright 2012 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkOffsetImageFilter_DEFINED
 #define SkOffsetImageFilter_DEFINED
 
 #include "SkImageFilter.h"
 #include "SkPoint.h"
 
 class SK_API SkOffsetImageFilter : public SkImageFilter {

[robertphillips, 2015/10/06 11:43:12]

Move this down to explicit private section ?

[reed1, 2015/10/06 16:59:24]

Done.

     typedef SkImageFilter INHERITED;
 
 public:
-    static SkOffsetImageFilter* Create(SkScalar dx, SkScalar dy, SkImageFilter* input = NULL,
-                                       const CropRect* cropRect = NULL) {
+    static SkImageFilter* Create(SkScalar dx, SkScalar dy, SkImageFilter* input = NULL,
+                                 const CropRect* cropRect = NULL) {
         if (!SkScalarIsFinite(dx) || !SkScalarIsFinite(dy)) {
             return NULL;
         }
         return new SkOffsetImageFilter(dx, dy, input, cropRect);
     }
     void computeFastBounds(const SkRect& src, SkRect* dst) const override;
     SK_TO_STRING_OVERRIDE()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkOffsetImageFilter)
 
 protected:
-    SkOffsetImageFilter(SkScalar dx, SkScalar dy, SkImageFilter* input, const CropRect* cropRect);
     void flatten(SkWriteBuffer&) const override;
-
-    virtual bool onFilterImage(Proxy*, const SkBitmap& src, const Context&,
-                               SkBitmap* result, SkIPoint* loc) const override;
+    bool onFilterImage(Proxy*, const SkBitmap& src, const Context&, SkBitmap* result,
+                       SkIPoint* loc) const override;
     bool onFilterBounds(const SkIRect&, const SkMatrix&, SkIRect*) const override;
 
 private:
+    SkOffsetImageFilter(SkScalar dx, SkScalar dy, SkImageFilter* input, const CropRect*);
+
     SkVector fOffset;
 };
 
 #endif