Make GrFontScaler not be ref-counted

src/gpu/text/GrFontScaler.h

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrFontScaler_DEFINED
 #define GrFontScaler_DEFINED
 
@@ skipping 25 matching lines @@
 
     typedef SkRefCnt INHERITED;
 };
 
 /*
  *  This is Gr's interface to the host platform's font scaler.
  *
  *  The client is responsible for instantiating this. The instance is created
  *  for a specific font+size+matrix.
  */
-class GrFontScaler : public SkRefCnt {
+class GrFontScaler final : public SkNoncopyable {
 public:
     explicit GrFontScaler(SkGlyphCache* strike);
-    virtual ~GrFontScaler();
+    ~GrFontScaler();
 
     const GrFontDescKey* getKey();
     GrMaskFormat getMaskFormat() const;
     GrMaskFormat getPackedGlyphMaskFormat(const SkGlyph&) const;
     bool getPackedGlyphBounds(const SkGlyph&, SkIRect* bounds);
     bool getPackedGlyphImage(const SkGlyph&, int width, int height, int rowBytes,
                              GrMaskFormat expectedMaskFormat, void* image);
     bool getPackedGlyphDFBounds(const SkGlyph&, SkIRect* bounds);
     bool getPackedGlyphDFImage(const SkGlyph&, int width, int height, void* image);
     const SkPath* getGlyphPath(const SkGlyph&);
     const SkGlyph& grToSkGlyph(GrGlyph::PackedID);
 
 private:
+    // The SkGlyphCache actually owns this GrFontScaler. The GrFontScaler is deleted when the
+    // SkGlyphCache is deleted.
     SkGlyphCache*  fStrike;
     GrFontDescKey* fKey;
 
-    typedef SkRefCnt INHERITED;
+    typedef SkNoncopyable INHERITED;
 };
 
 #endif