Dynamically allocate the GrDrawContexts

include/gpu/GrDrawContext.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrDrawContext_DEFINED
 #define GrDrawContext_DEFINED
 
@@ skipping 245 matching lines @@
      *
      * @param paint    describes how to color pixels.
      * @param batch    the batch to draw
      */
     void drawBatch(GrRenderTarget*, const GrClip&, const GrPaint&, GrDrawBatch*);
 
 private:
     friend class GrAtlasTextContext; // for access to drawBatch
     friend class GrContext; // for ctor
 
-    GrDrawContext(GrContext*, GrDrawTarget*, const SkSurfaceProps&);
-
-    GrTextContext* createTextContext(GrRenderTarget*, const SkSurfaceProps&);
+    GrDrawContext(GrContext*, GrDrawTarget*, const SkSurfaceProps* surfaceProps);
 
     // Checks if the context has been abandoned and if the rendertarget is owned by this context
     bool prepareToDraw(GrRenderTarget* rt);
 
     void internalDrawPath(GrDrawTarget*,
                           GrPipelineBuilder*,
                           const SkMatrix& viewMatrix,
                           GrColor,
                           bool useAA,
                           const SkPath&,
                           const GrStrokeInfo&);
 
     // This entry point allows the GrTextContext-derived classes to add their batches to
     // the drawTarget.
     void drawBatch(GrPipelineBuilder* pipelineBuilder, GrDrawBatch* batch);
 
     GrContext*          fContext;     // owning context -> no ref
     GrDrawTarget*       fDrawTarget;
-    GrTextContext*      fTextContext; // lazily created
+    GrTextContext*      fTextContext; // lazily gotten from GrContext::DrawingMgr
 
     SkSurfaceProps      fSurfaceProps;
 };
 
 #endif