Remove unused includes of plugin_list.h. Also remove unused ContentClient and webkit_support method…

webkit/support/test_webplugin_page_delegate.h

-// Copyright (c) 2012 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_SUPPORT_TEST_WEBPLUGIN_PAGE_DELEGATE_H_
-#define WEBKIT_SUPPORT_TEST_WEBPLUGIN_PAGE_DELEGATE_H_
-
-#include <string>
-
-#include "webkit/plugins/npapi/webplugin_delegate_impl.h"
-#include "webkit/plugins/npapi/webplugin_page_delegate.h"
-
-namespace webkit_support {
-
-class TestWebPluginPageDelegate : public webkit::npapi::WebPluginPageDelegate {
- public:
-  TestWebPluginPageDelegate() {}
-  virtual ~TestWebPluginPageDelegate() {}
-
-  virtual webkit::npapi::WebPluginDelegate* CreatePluginDelegate(
-      const base::FilePath& file_path,
-      const std::string& mime_type) OVERRIDE;
-  virtual WebKit::WebPlugin* CreatePluginReplacement(
-      const base::FilePath& file_path) OVERRIDE;
-  virtual void CreatedPluginWindow(gfx::PluginWindowHandle handle) OVERRIDE {}
-  virtual void WillDestroyPluginWindow(
-      gfx::PluginWindowHandle handle) OVERRIDE {}
-  virtual void DidMovePlugin(
-      const webkit::npapi::WebPluginGeometry& move) OVERRIDE {}
-  virtual void DidStartLoadingForPlugin() OVERRIDE {}
-  virtual void DidStopLoadingForPlugin() OVERRIDE {}
-  virtual WebKit::WebCookieJar* GetCookieJar() OVERRIDE;
-};
-
-}  // namespace webkit_support
-
-#endif  // WEBKIT_SUPPORT_TEST_WEBPLUGIN_PAGE_DELEGATE_H_