Address google3 compiler warning

https://codereview.appspot.com/7308063/



git-svn-id: http://skia.googlecode.com/svn/trunk@7655 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/bench/DeferredCanvasBench.cpp b/bench/DeferredCanvasBench.cpp
index a1a3901..98a1e60 100644
--- a/bench/DeferredCanvasBench.cpp
+++ b/bench/DeferredCanvasBench.cpp
@@ -63,6 +63,8 @@
     virtual void flushedDrawCommands() SK_OVERRIDE {fDummy = !fDummy;}
 private:
     bool fDummy;
+
+    typedef SkDeferredCanvas::NotificationClient INHERITED;
 };
 
 // Test that records very simple draw operations.