ash: Convert ShelfDelegate to use WmShelf* instead of Shelf*

ash/common/shelf/shelf.cc

 // Copyright 2013 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/common/shelf/shelf.h"
 
 #include "ash/common/shelf/shelf_delegate.h"
 #include "ash/common/shelf/shelf_item_delegate.h"
 #include "ash/common/shelf/shelf_model.h"
 #include "ash/common/shelf/shelf_navigator.h"
@@ skipping 14 matching lines @@
              ShelfWidget* shelf_widget)
     : wm_shelf_(wm_shelf),
       shelf_widget_(shelf_widget),
       shelf_view_(shelf_view) {
   DCHECK(wm_shelf_);
   DCHECK(shelf_view_);
   DCHECK(shelf_widget_);
 }
 
 Shelf::~Shelf() {
-  WmShell::Get()->shelf_delegate()->OnShelfDestroyed(this);
+  WmShell::Get()->shelf_delegate()->OnShelfDestroyed(wm_shelf_);
 }
 
 // static
 Shelf* Shelf::ForPrimaryDisplay() {
   return Shelf::ForWindow(WmShell::Get()->GetPrimaryRootWindow());
 }
 
 // static
 Shelf* Shelf::ForWindow(WmWindow* window) {
   return window->GetRootWindowController()->GetShelf()->shelf();
@@ skipping 72 matching lines @@
 
 app_list::ApplicationDragAndDropHost* Shelf::GetDragAndDropHostForAppList() {
   return shelf_view_;
 }
 
 void Shelf::UpdateShelfItemBackground(int alpha) {
   shelf_view_->UpdateShelfItemBackground(alpha);
 }
 
 }  // namespace ash