Change GrTextContext fallbacks to be a linked list chain.

src/gpu/GrStencilAndCoverTextContext.h

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrStencilAndCoverTextContext_DEFINED
 #define GrStencilAndCoverTextContext_DEFINED
 
 #include "GrTextContext.h"
 #include "GrDrawState.h"
 #include "GrDrawTarget.h"
 #include "SkStrokeRec.h"
 
 class GrTextStrike;
 class GrPath;
 class GrPathRange;
 
 /*
  * This class implements text rendering using stencil and cover path rendering
  * (by the means of GrDrawTarget::drawPath).
  * This class exposes the functionality through GrTextContext interface.
  */
 class GrStencilAndCoverTextContext : public GrTextContext {
 public:
-    GrStencilAndCoverTextContext(GrContext*, const SkDeviceProperties&);
+    static GrStencilAndCoverTextContext* Create(GrContext*, const SkDeviceProperties&);
+
     virtual ~GrStencilAndCoverTextContext();
 
-    virtual bool canDraw(const SkPaint& paint) SK_OVERRIDE;
-
-    virtual void drawText(const GrPaint&, const SkPaint&, const char text[],
-                          size_t byteLength,
-                          SkScalar x, SkScalar y) SK_OVERRIDE;
-    virtual void drawPosText(const GrPaint&, const SkPaint&,
-                             const char text[], size_t byteLength,
-                             const SkScalar pos[], int scalarsPerPosition,
-                             const SkPoint& offset) SK_OVERRIDE;
-
 private:
     static const int kGlyphBufferSize = 1024;
 
     enum RenderMode {
         /**
          * This is the render mode used by drawText(), which is mainly used by
          * the Skia unit tests. It tries match the other text backends exactly,
          * with the exception of not implementing LCD text, and doing anti-
          * aliasing with the built-in MSAA.
          */
@@ skipping 16 matching lines @@
     float                           fTextInverseRatio;
     SkGlyphCache*                   fGlyphCache;
     GrPathRange*                    fGlyphs;
     uint32_t                        fIndexBuffer[kGlyphBufferSize];
     float                           fTransformBuffer[2 * kGlyphBufferSize];
     GrDrawTarget::PathTransformType fTransformType;
     int                             fPendingGlyphCount;
     SkMatrix                        fContextInitialMatrix;
     bool                            fNeedsDeviceSpaceGlyphs;
 
+    GrStencilAndCoverTextContext(GrContext*, const SkDeviceProperties&);
+
+    virtual bool canDraw(const SkPaint& paint) SK_OVERRIDE;
+
+    virtual void onDrawText(const GrPaint&, const SkPaint&, const char text[],
+                            size_t byteLength,
+                            SkScalar x, SkScalar y) SK_OVERRIDE;
+    virtual void onDrawPosText(const GrPaint&, const SkPaint&,
+                               const char text[], size_t byteLength,
+                               const SkScalar pos[], int scalarsPerPosition,
+                               const SkPoint& offset) SK_OVERRIDE;
+
     void init(const GrPaint&, const SkPaint&, size_t textByteLength,
               RenderMode, const SkPoint& textTranslate);
     void initGlyphs(SkGlyphCache* cache);
     void appendGlyph(uint16_t glyphID, float x);
     void appendGlyph(uint16_t glyphID, float x, float y);
     void flush();
     void finish();
 
 };
 
 #endif