GrContext::copyTexture->GrContext::copySurface. Add a flush writes pixel ops flag.

include/gpu/GrSurface.h

Index: include/gpu/GrSurface.h
diff --git a/include/gpu/GrSurface.h b/include/gpu/GrSurface.h
index 23311a2f523e28448a6bf8f17ac7d3e2589a7ecd..0bbf8d9c12a0ee4eac5fcc7de6c57b2057a02e7d 100644
--- a/include/gpu/GrSurface.h
+++ b/include/gpu/GrSurface.h
@@ -112,6 +112,11 @@ public:
                              size_t rowBytes = 0,
                              uint32_t pixelOpsFlags = 0) = 0;
 
+    /**
+     * After this returns any pending writes to the surface will be issued to the backend 3D API.
+     */
+    void flushWrites();
+
     /** Access methods that are only to be used within Skia code. */
     inline GrSurfacePriv surfacePriv();
     inline const GrSurfacePriv surfacePriv() const;