Revert of factories should return baseclass, allowing the impl to specialize

include/effects/SkTableMaskFilter.h

 /*
  * Copyright 2006 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 SkTableMaskFilter_DEFINED
 #define SkTableMaskFilter_DEFINED
 
 #include "SkMaskFilter.h"
 #include "SkScalar.h"
 
 /** \class SkTableMaskFilter
 
     Applies a table lookup on each of the alpha values in the mask.
     Helper methods create some common tables (e.g. gamma, clipping)
  */
 class SK_API SkTableMaskFilter : public SkMaskFilter {
 public:
+    virtual ~SkTableMaskFilter();
+
     /** Utility that sets the gamma table
      */
     static void MakeGammaTable(uint8_t table[256], SkScalar gamma);
 
     /** Utility that creates a clipping table: clamps values below min to 0
         and above max to 255, and rescales the remaining into 0..255
      */
     static void MakeClipTable(uint8_t table[256], uint8_t min, uint8_t max);
 
-    static SkMaskFilter* Create(const uint8_t table[256]) {
+    static SkTableMaskFilter* Create(const uint8_t table[256]) {
         return new SkTableMaskFilter(table);
     }
 
-    static SkMaskFilter* CreateGamma(SkScalar gamma) {
+    static SkTableMaskFilter* CreateGamma(SkScalar gamma) {
         uint8_t table[256];
         MakeGammaTable(table, gamma);
         return new SkTableMaskFilter(table);
     }
 
-    static SkMaskFilter* CreateClip(uint8_t min, uint8_t max) {
+    static SkTableMaskFilter* CreateClip(uint8_t min, uint8_t max) {
         uint8_t table[256];
         MakeClipTable(table, min, max);
         return new SkTableMaskFilter(table);
     }
 
     SkMask::Format getFormat() const override;
-    bool filterMask(SkMask*, const SkMask&, const SkMatrix&, SkIPoint*) const override;
+    virtual bool filterMask(SkMask*, const SkMask&, const SkMatrix&,
+                            SkIPoint*) const override;
 
     SK_TO_STRING_OVERRIDE()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTableMaskFilter)
 
 protected:
-    virtual ~SkTableMaskFilter();
-
+    SkTableMaskFilter();
+    explicit SkTableMaskFilter(const uint8_t table[256]);
     void flatten(SkWriteBuffer&) const override;
 
 private:
-    SkTableMaskFilter();
-    explicit SkTableMaskFilter(const uint8_t table[256]);
-
     uint8_t fTable[256];
 
     typedef SkMaskFilter INHERITED;
 };
 
 #endif