Cleanup shelf initialization and observation.

ash/shelf/shelf_alignment_menu.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/shelf/shelf_alignment_menu.h"
 
 #include "ash/metrics/user_metrics_recorder.h"
 #include "ash/shelf/shelf.h"
-#include "ash/shelf/shelf_layout_manager.h"
 #include "ash/shelf/shelf_types.h"
-#include "ash/shelf/shelf_widget.h"
 #include "ash/shell.h"
 #include "grit/ash_strings.h"
 #include "ui/aura/window.h"
 
 namespace ash {
 
 ShelfAlignmentMenu::ShelfAlignmentMenu(Shelf* shelf)
     : ui::SimpleMenuModel(nullptr), shelf_(shelf) {
   DCHECK(shelf_);
   int align_group_id = 1;
@@ skipping 22 matching lines @@
 }
 
 bool ShelfAlignmentMenu::GetAcceleratorForCommandId(
     int command_id,
     ui::Accelerator* accelerator) {
   return false;
 }
 
 void ShelfAlignmentMenu::ExecuteCommand(int command_id, int event_flags) {
   Shell* shell = Shell::GetInstance();
-  ShelfLayoutManager* manager = shelf_->shelf_widget()->shelf_layout_manager();
   switch (static_cast<MenuItem>(command_id)) {
     case MENU_ALIGN_LEFT:
       shell->metrics()->RecordUserMetricsAction(UMA_SHELF_ALIGNMENT_SET_LEFT);
-      manager->SetAlignment(SHELF_ALIGNMENT_LEFT);
+      shelf_->SetAlignment(SHELF_ALIGNMENT_LEFT);
       break;
     case MENU_ALIGN_BOTTOM:
       shell->metrics()->RecordUserMetricsAction(UMA_SHELF_ALIGNMENT_SET_BOTTOM);
-      manager->SetAlignment(SHELF_ALIGNMENT_BOTTOM);
+      shelf_->SetAlignment(SHELF_ALIGNMENT_BOTTOM);
       break;
     case MENU_ALIGN_RIGHT:
       shell->metrics()->RecordUserMetricsAction(UMA_SHELF_ALIGNMENT_SET_RIGHT);
-      manager->SetAlignment(SHELF_ALIGNMENT_RIGHT);
+      shelf_->SetAlignment(SHELF_ALIGNMENT_RIGHT);
       break;
   }
 }
 
 }  // namespace ash