re-re-land of https://codereview.chromium.org/11364053/

ash/shell.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 <string>
 
 #include "ash/accelerators/focus_manager_factory.h"
@@ skipping 49 matching lines @@
 #include "ash/wm/visibility_controller.h"
 #include "ash/wm/window_cycle_controller.h"
 #include "ash/wm/window_modality_controller.h"
 #include "ash/wm/window_properties.h"
 #include "ash/wm/window_util.h"
 #include "ash/wm/workspace_controller.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/leak_annotations.h"
 #include "ui/aura/client/aura_constants.h"
+#include "ui/aura/client/stacking_client.h"
 #include "ui/aura/client/user_action_client.h"
 #include "ui/aura/display_manager.h"
 #include "ui/aura/env.h"
 #include "ui/aura/focus_manager.h"
 #include "ui/aura/layout_manager.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/ui_controls_aura.h"
 #include "ui/aura/window.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animator.h"
@@ skipping 368 matching lines @@
     touch_observer_hud_.reset(new internal::TouchObserverHUD);
     AddPreTargetHandler(touch_observer_hud_.get());
   }
 
   mouse_cursor_filter_.reset(new internal::MouseCursorEventFilter());
   AddPreTargetHandler(mouse_cursor_filter_.get());
 
   // Create Controllers that may need root window.
   // TODO(oshima): Move as many controllers before creating
   // RootWindowController as possible.
-  stacking_controller_.reset(new internal::StackingController);
+  stacking_client_.reset(delegate_->CreateStackingClient());
+  if (stacking_client_.get())
+    aura::client::SetStackingClient(stacking_client_.get());
   visibility_controller_.reset(new internal::VisibilityController);
   drag_drop_controller_.reset(new internal::DragDropController);
   user_action_client_.reset(delegate_->CreateUserActionClient());
   window_modality_controller_.reset(new internal::WindowModalityController);
   AddPreTargetHandler(window_modality_controller_.get());
 
   magnification_controller_.reset(
       internal::MagnificationController::CreateInstance());
 
   high_contrast_controller_.reset(new HighContrastController);
@@ skipping 288 matching lines @@
   root->ShowRootWindow();
   // Activate new root for testing.
   active_root_window_ = root;
 }
 
 void Shell::DoInitialWorkspaceAnimation() {
   return GetPrimaryRootWindowController()->workspace_controller()->
       DoInitialAnimation();
 }
 
+aura::client::StackingClient* Shell::stacking_client() {
+  return stacking_client_.get();
+}
+
 void Shell::InitRootWindowController(
     internal::RootWindowController* controller) {
   aura::RootWindow* root_window = controller->root_window();
   DCHECK(activation_controller_.get());
   DCHECK(visibility_controller_.get());
   DCHECK(drag_drop_controller_.get());
   DCHECK(capture_controller_.get());
   DCHECK(window_cycle_controller_.get());
 
   root_window->set_focus_manager(focus_manager_.get());
@@ skipping 51 matching lines @@
 
 bool Shell::CanAcceptEvents() {
   return true;
 }
 
 ui::EventTarget* Shell::GetParentTarget() {
   return NULL;
 }
 
 }  // namespace ash