Make ToplevelWindowEventFilter and WorkspaceEventFilter into event handlers.

ash/wm/workspace/workspace_event_filter_test_helper.h

Index: ash/wm/workspace/workspace_event_filter_test_helper.h
===================================================================
--- ash/wm/workspace/workspace_event_filter_test_helper.h	(revision 155914)
+++ ash/wm/workspace/workspace_event_filter_test_helper.h	(working copy)
@@ -1,31 +0,0 @@
-// 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 ASH_WM_WORKSPACE_WORKSPACE_EVENT_FILTER_TEST_HELPER_H_
-#define ASH_WM_WORKSPACE_WORKSPACE_EVENT_FILTER_TEST_HELPER_H_
-
-#include "ash/wm/workspace/workspace_event_filter.h"
-
-namespace ash {
-namespace internal {
-
-class WorkspaceEventFilterTestHelper {
- public:
-  explicit WorkspaceEventFilterTestHelper(WorkspaceEventFilter* filter);
-  ~WorkspaceEventFilterTestHelper();
-
-  MultiWindowResizeController* resize_controller() {
-    return &(filter_->multi_window_resize_controller_);
-  }
-
- private:
-  WorkspaceEventFilter* filter_;
-
-  DISALLOW_COPY_AND_ASSIGN(WorkspaceEventFilterTestHelper);
-};
-
-}  // namespace internal
-}  // namespace ash
-
-#endif  // ASH_WM_WORKSPACE_WORKSPACE_EVENT_FILTER_TEST_HELPER_H_