Add glCopyTexSubImage2D to GrGLInterface

src/gpu/gl/GrGLInterface.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "gl/GrGLInterface.h"
 #include "gl/GrGLExtensions.h"
@@ skipping 41 matching lines @@
         NULL == fBindTexture ||
         NULL == fBlendFunc ||
         NULL == fBlendColor ||      // -> GL >= 1.4, ES >= 2.0 or extension
         NULL == fBufferData ||
         NULL == fBufferSubData ||
         NULL == fClear ||
         NULL == fClearColor ||
         NULL == fClearStencil ||
         NULL == fColorMask ||
         NULL == fCompileShader ||
+#if 0  //  FIXME: Remove this once Chromium is updated to provide this function
+        NULL == fCopyTexSubImage2D ||
+#endif
         NULL == fCreateProgram ||
         NULL == fCreateShader ||
         NULL == fCullFace ||
         NULL == fDeleteBuffers ||
         NULL == fDeleteProgram ||
         NULL == fDeleteShader ||
         NULL == fDeleteTextures ||
         NULL == fDepthMask ||
         NULL == fDisable ||
         NULL == fDisableVertexAttribArray ||
@@ skipping 296 matching lines @@
             if (NULL == fBindVertexArray ||
                 NULL == fDeleteVertexArrays ||
                 NULL == fGenVertexArrays) {
                 return false;
             }
         }
     }
 
     return true;
 }