Remove the GrGLInterface callback mechanism.

include/gpu/gl/GrGLInterface.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 GrGLInterface_DEFINED
 #define GrGLInterface_DEFINED
 
@@ skipping 58 matching lines @@
  * CPU overhead.
  */
 const SK_API GrGLInterface* GrGLCreateNullInterface();
 
 /**
  * Creates a debugging GrGLInterface that doesn't draw anything. Used for
  * finding memory leaks and invalid memory accesses.
  */
 const GrGLInterface* GrGLCreateDebugInterface();
 
-#if GR_GL_PER_GL_FUNC_CALLBACK
-typedef void (*GrGLInterfaceCallbackProc)(const GrGLInterface*);
-typedef intptr_t GrGLInterfaceCallbackData;
-#endif
-
 /** Function that returns a new interface identical to "interface" but without support for
     GL_NV_path_rendering. */
 const GrGLInterface* GrGLInterfaceRemoveNVPR(const GrGLInterface*);
 
 /** Function that returns a new interface identical to "interface" but with support for
     test version of GL_EXT_debug_marker. */
 const GrGLInterface* GrGLInterfaceAddTestDebugMarker(const GrGLInterface*,
                                                      GrGLInsertEventMarkerProc insertEventMarkerFn,
                                                      GrGLPushGroupMarkerProc pushGroupMarkerFn,
                                                      GrGLPopGroupMarkerProc popGroupMarkerFn);
@@ skipping 391 matching lines @@
         GrGLFunction<GrGLGetDebugMessageLogProc> fGetDebugMessageLog;
         GrGLFunction<GrGLPushDebugGroupProc> fPushDebugGroup;
         GrGLFunction<GrGLPopDebugGroupProc> fPopDebugGroup;
         GrGLFunction<GrGLObjectLabelProc> fObjectLabel;
 
         /* EGL functions */
         GrGLFunction<GrEGLCreateImageProc> fEGLCreateImage;
         GrGLFunction<GrEGLDestroyImageProc> fEGLDestroyImage;
     } fFunctions;
 
-    // Per-GL func callback
-#if GR_GL_PER_GL_FUNC_CALLBACK
-    GrGLInterfaceCallbackProc fCallback;
-    GrGLInterfaceCallbackData fCallbackData;
-#endif
-
     // This exists for internal testing.
     virtual void abandon() const {}
 };
 
 #endif