cc: Avoid extra flush calls to Skia GrContext

cc/resources/resource_provider.h

Index: cc/resources/resource_provider.h
diff --git a/cc/resources/resource_provider.h b/cc/resources/resource_provider.h
index f79ac190fa2164795aebffd83c6c1cf345d9ad68..a5653ea5b9b2b16325996b9ae77d1206fbcd6663 100644
--- a/cc/resources/resource_provider.h
+++ b/cc/resources/resource_provider.h
@@ -42,6 +42,7 @@
 #include "ui/gfx/gpu_memory_buffer.h"
 
 class GrContext;
+class GrSurface;
 
 namespace gpu {
 class GpuMemoryBufferManager;
@@ -351,6 +352,7 @@ class CC_EXPORT ResourceProvider
     ResourceProvider::Resource* resource_;
     base::ThreadChecker thread_checker_;
     skia::RefPtr<SkSurface> sk_surface_;
+    skia::RefPtr<GrSurface> gr_surface_;
 
     DISALLOW_COPY_AND_ASSIGN(ScopedWriteLockGr);
   };