Remove unused paintScrollbarThumb impl.

content/shell/renderer/test_runner/test_interfaces.h

 // Copyright 2014 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 CONTENT_SHELL_RENDERER_TEST_RUNNER_TEST_INTERFACES_H_
 #define CONTENT_SHELL_RENDERER_TEST_RUNNER_TEST_INTERFACES_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "content/shell/renderer/test_runner/mock_web_theme_engine.h"
 #include "third_party/WebKit/public/platform/WebNonCopyable.h"
 
-#if defined(OS_MACOSX)
-#include "content/shell/renderer/test_runner/mock_web_theme_engine_mac.h"
-#else
-#include "content/shell/renderer/test_runner/mock_web_theme_engine.h"
-#endif
-
 namespace blink {
 class WebFrame;
 class WebThemeEngine;
 class WebURL;
 class WebView;
 }
 
 namespace content {
 
 class AccessibilityController;
@@ skipping 32 matching lines @@
  private:
   scoped_ptr<AccessibilityController> accessibility_controller_;
   scoped_ptr<EventSender> event_sender_;
   base::WeakPtr<GamepadController> gamepad_controller_;
   scoped_ptr<TextInputController> text_input_controller_;
   scoped_ptr<TestRunner> test_runner_;
   WebTestDelegate* delegate_;
   WebTestProxyBase* proxy_;
 
   std::vector<WebTestProxyBase*> window_list_;
-#if defined(OS_MACOSX)
-  scoped_ptr<MockWebThemeEngineMac> theme_engine_;
-#else
   scoped_ptr<MockWebThemeEngine> theme_engine_;
-#endif
 
   DISALLOW_COPY_AND_ASSIGN(TestInterfaces);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_SHELL_RENDERER_TEST_RUNNER_TEST_INTERFACES_H_