Add OVERRIDE to webkit/.

webkit/plugins/npapi/test/plugin_delete_plugin_in_stream_test.h

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef WEBKIT_PLUGINS_NPAPI_TEST_PLUGIN_DELETE_PLUGIN_IN_STREAM_TEST_H_
 #define WEBKIT_PLUGINS_NPAPI_TEST_PLUGIN_DELETE_PLUGIN_IN_STREAM_TEST_H_
 
+#include "base/compiler_specific.h"
 #include "webkit/plugins/npapi/test/plugin_test.h"
 
 namespace NPAPIClient {
 
 // This class tests
 class DeletePluginInStreamTest : public PluginTest {
  public:
   // Constructor.
   DeletePluginInStreamTest(NPP id, NPNetscapeFuncs *host_functions);
   //
   // NPAPI functions
   //
-  virtual NPError SetWindow(NPWindow* pNPWindow);
+  virtual NPError SetWindow(NPWindow* pNPWindow) OVERRIDE;
   virtual NPError NewStream(NPMIMEType type, NPStream* stream,
-                            NPBool seekable, uint16* stype);
+                            NPBool seekable, uint16* stype) OVERRIDE;
  private:
   bool test_started_;
   std::string self_url_;
 };
 
 }  // namespace NPAPIClient
 
 #endif  // WEBKIT_PLUGINS_NPAPI_TEST_PLUGIN_DELETE_PLUGIN_IN_STREAM_TEST_H_