compositor_unittests target is unimplmented on Mac

ui/gfx/compositor/test_suite.h

 // 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 UI_GFX_COMPOSITOR_TEST_SUITE_H_
 #define UI_GFX_COMPOSITOR_TEST_SUITE_H_
 #pragma once
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/test/test_suite.h"
 
 namespace ui {
 class WebKitPlatformSupportImpl;
 }  // namespace ui
 
 class MessageLoop;
 
 class CompositorTestSuite : public base::TestSuite {
  public:
   CompositorTestSuite(int argc, char** argv);
-  ~CompositorTestSuite();
+  virtual ~CompositorTestSuite();
 
  protected:
   // base::TestSuite:
   virtual void Initialize() OVERRIDE;
   virtual void Shutdown() OVERRIDE;
 
  private:
   scoped_ptr<MessageLoop> message_loop_;
 };
 
 #endif  // UI_GFX_COMPOSITOR_TEST_SUITE_H_