mash: Move WmShelfAura ownership to RootWindowController and init it earlier

ash/shelf/shelf_widget.cc

 // Copyright 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/shelf/shelf_widget.h"
 
 #include "ash/ash_switches.h"
+#include "ash/aura/wm_shelf_aura.h"
 #include "ash/aura/wm_window_aura.h"
 #include "ash/common/shelf/shelf_constants.h"
 #include "ash/common/shelf/wm_shelf_util.h"
 #include "ash/common/shell_window_ids.h"
 #include "ash/common/wm_root_window_controller.h"
 #include "ash/focus_cycler.h"
 #include "ash/session/session_state_delegate.h"
 #include "ash/shelf/shelf_delegate.h"
 #include "ash/shelf/shelf_layout_manager.h"
 #include "ash/shelf/shelf_model.h"
@@ skipping 690 matching lines @@
   // status area background, app list button and overflow button.
   if (shelf_)
     shelf_->SchedulePaint();
   status_area_widget_->SchedulePaint();
 }
 
 bool ShelfWidget::GetDimsShelf() const {
   return delegate_view_->GetDimmed();
 }
 
-void ShelfWidget::CreateShelf() {
+void ShelfWidget::CreateShelf(WmShelfAura* wm_shelf_aura) {
   DCHECK(!shelf_);
 
   Shell* shell = Shell::GetInstance();
   ShelfDelegate* delegate = shell->GetShelfDelegate();
   shelf_.reset(new Shelf(shell->shelf_model(), delegate, this));
+  // Must be initialized before the delegate is notified because the delegate
+  // may try to access the WmShelf.
+  wm_shelf_aura->SetShelf(shelf_.get());
   delegate->OnShelfCreated(shelf_.get());
 
   SetFocusCycler(shell->focus_cycler());
 }
 
 void ShelfWidget::PostCreateShelf() {
   shelf_->SetVisible(Shell::GetInstance()
                          ->session_state_delegate()
                          ->IsActiveUserSessionStarted());
   shelf_layout_manager_->LayoutShelf();
@@ skipping 76 matching lines @@
     shelf_layout_manager_->UpdateAutoHideForMouseEvent(event);
 }
 
 void ShelfWidget::OnGestureEvent(ui::GestureEvent* event) {
   Widget::OnGestureEvent(event);
   if (Shell::GetInstance()->in_mus() && shelf_layout_manager_)
     shelf_layout_manager_->UpdateAutoHideForGestureEvent(event);
 }
 
 }  // namespace ash