Make ToplevelWindowEventFilter and WorkspaceEventFilter into event handlers.

ash/shell_unittest.cc

 // 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.
 
 #include "ash/shell.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "ash/ash_switches.h"
@@ skipping 282 matching lines @@
   //  EXPECT_FALSE(background->layer());
 
   // Create a normal window.  It is not maximized.
   views::Widget::InitParams widget_params(
       views::Widget::InitParams::TYPE_WINDOW);
   widget_params.bounds.SetRect(11, 22, 300, 400);
   views::Widget* widget = CreateTestWindow(widget_params);
   widget->Show();
   EXPECT_FALSE(widget->IsMaximized());
 
-  // We have a default container event filter (for window drags).
-  EXPECT_TRUE(widget->GetNativeWindow()->parent()->event_filter());
-
   // Clean up.
   widget->Close();
 }
 
 TEST_F(ShellTest, FullscreenWindowHidesShelf) {
   ExpectAllContainers();
 
   // Create a normal window.  It is not maximized.
   views::Widget::InitParams widget_params(
       views::Widget::InitParams::TYPE_WINDOW);
@@ skipping 92 matching lines @@
  private:
   DISALLOW_COPY_AND_ASSIGN(ShellTest2);
 };
 
 TEST_F(ShellTest2, DontCrashWhenWindowDeleted) {
   window_.reset(new aura::Window(NULL));
   window_->Init(ui::LAYER_NOT_DRAWN);
 }
 
 }  // namespace ash