Add hooks for GL_EXT_debug_marker in gpu

src/gpu/GrInOrderDrawBuffer.h

Index: src/gpu/GrInOrderDrawBuffer.h
diff --git a/src/gpu/GrInOrderDrawBuffer.h b/src/gpu/GrInOrderDrawBuffer.h
index 6b680b2d555e99ce2406d7e092835edb980508eb..bc2d81eaa794edf7ce6e81f77da0cfef1bf86cff 100644
--- a/src/gpu/GrInOrderDrawBuffer.h
+++ b/src/gpu/GrInOrderDrawBuffer.h
@@ -168,6 +168,11 @@ private:
 
     bool quickInsideClip(const SkRect& devBounds);
 
+    virtual void onInsertEventMarker(const char* marker) SK_OVERRIDE;
+    virtual void onPushGroupMarker(const char* marker) SK_OVERRIDE;
+    virtual void onPopGroupMarker() SK_OVERRIDE;
+
+
     // Attempts to concat instances from info onto the previous draw. info must represent an
     // instanced draw. The caller must have already recorded a new draw state and clip if necessary.
     int concatInstancedDraw(const DrawInfo& info);