Add swapBuffer call to SkGLContextHelper.

include/gpu/gl/SkMesaGLContext.h

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef SkMesaGLContext_DEFINED
 #define SkMesaGLContext_DEFINED
 
 #include "SkGLContextHelper.h"
 
 #if SK_MESA
 
 class SkMesaGLContext : public SkGLContextHelper {
 private:
     typedef intptr_t Context;
 
 public:
     SkMesaGLContext();
 
     virtual ~SkMesaGLContext();
 
     virtual void makeCurrent() const SK_OVERRIDE;
+    virtual void swapBuffers() const SK_OVERRIDE;
 
     class AutoContextRestore {
     public:
         AutoContextRestore();
         ~AutoContextRestore();
 
     private:
         Context fOldContext;
         GrGLint fOldWidth;
         GrGLint fOldHeight;
         GrGLint fOldFormat;
         void*   fOldImage;
     };
 
 protected:
     virtual const GrGLInterface* createGLContext() SK_OVERRIDE;
     virtual void destroyGLContext() SK_OVERRIDE;
 
 private:
     Context fContext;
     GrGLubyte *fImage;
 };
 
 #endif
 
 #endif