Add a shallow command buffer flush that doesn't glFlush

webkit/gpu/webgraphicscontext3d_in_process_impl.h

Index: webkit/gpu/webgraphicscontext3d_in_process_impl.h
diff --git a/webkit/gpu/webgraphicscontext3d_in_process_impl.h b/webkit/gpu/webgraphicscontext3d_in_process_impl.h
index 1be900ebf27f57d92409667fb048435c71581e23..293dd05699f508127b3e97a0b518f612278dd498 100644
--- a/webkit/gpu/webgraphicscontext3d_in_process_impl.h
+++ b/webkit/gpu/webgraphicscontext3d_in_process_impl.h
@@ -478,6 +478,10 @@ class WebGraphicsContext3DInProcessImpl : public WebGraphicsContext3D {
   virtual void bindUniformLocationCHROMIUM(WebGLId program, WGC3Dint location,
                                            const WGC3Dchar* uniform);
 
+  // CHROMIUM_shallow_flush
+  // Only applies to contexts that use the command buffer.
+  virtual void shallowFlushCHROMIUM() { }
+
  protected:
   virtual GrGLInterface* onCreateGrGLInterface();