GrGLInterface: Add support for NV_framebuffer_mixed_samples

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 330 matching lines @@
         GLPtr<GrGLCoverFillPathInstancedProc> fCoverFillPathInstanced;
         GLPtr<GrGLCoverStrokePathInstancedProc> fCoverStrokePathInstanced;
         // NV_path_rendering v1.2
         GLPtr<GrGLStencilThenCoverFillPathProc> fStencilThenCoverFillPath;
         GLPtr<GrGLStencilThenCoverStrokePathProc> fStencilThenCoverStrokePath;
         GLPtr<GrGLStencilThenCoverFillPathInstancedProc> fStencilThenCoverFillPathInstanced;
         GLPtr<GrGLStencilThenCoverStrokePathInstancedProc> fStencilThenCoverStrokePathInstanced;
         // NV_path_rendering v1.3
         GLPtr<GrGLProgramPathFragmentInputGenProc> fProgramPathFragmentInputGen;
         GLPtr<GrGLPathMemoryGlyphIndexArrayProc> fPathMemoryGlyphIndexArray;
+        // NV_framebuffer_mixed_samples
+        GLPtr<GrGLCoverageModulationProc> fCoverageModulation;
     } 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