Revert 177182 - ViewTest.ChangeNativeViewHierarchyFindRoots failure

ui/aura/env.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 UI_AURA_ENV_H_
 #define UI_AURA_ENV_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/observer_list.h"
 #include "ui/aura/aura_export.h"
+#include "ui/aura/client/stacking_client.h"
 #include "ui/base/events/event_handler.h"
 #include "ui/base/events/event_target.h"
 #include "ui/gfx/point.h"
 
 #if defined(USE_X11)
 #include "ui/aura/device_list_updater_aurax11.h"
 #endif
 
 namespace aura {
 class EnvObserver;
@@ skipping 34 matching lines @@
   bool is_touch_down() const { return is_touch_down_; }
   void set_touch_down(bool value) { is_touch_down_ = value; }
 
   // Whether RenderWidgetHostViewAura::OnPaint() should paint white background
   // when backing store is not present. Default is true.
   // In some cases when page is using transparent background painting white
   // background before backing store is initialized causes a white splash.
   bool render_white_bg() const { return render_white_bg_; }
   void set_render_white_bg(bool value) { render_white_bg_ = value; }
 
+  client::StackingClient* stacking_client() { return stacking_client_; }
+  void set_stacking_client(client::StackingClient* stacking_client) {
+    stacking_client_ = stacking_client;
+  }
+
   // Returns the native event dispatcher. The result should only be passed to
   // base::RunLoop(dispatcher), or used to dispatch an event by
   // |Dispatch(const NativeEvent&)| on it. It must never be stored.
 #if !defined(OS_MACOSX)
   MessageLoop::Dispatcher* GetDispatcher();
 #endif
 
   // Invoked by RootWindow when its host is activated.
   void RootWindowActivated(RootWindow* root_window);
 
@@ skipping 13 matching lines @@
 #if !defined(USE_X11)
   scoped_ptr<MessageLoop::Dispatcher> dispatcher_;
 #endif
 
   static Env* instance_;
   int mouse_button_flags_;
   // Location of last mouse event, in screen coordinates.
   gfx::Point last_mouse_location_;
   bool is_touch_down_;
   bool render_white_bg_;
+  client::StackingClient* stacking_client_;
 
 #if defined(USE_X11)
   DeviceListUpdaterAuraX11 device_list_updater_aurax11_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(Env);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_ENV_H_