Replace ShelfItemDelegate::GetTitle() with ShelfItem::title.

ash/common/test/test_shelf_item_delegate.h

 // 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.
 
 #ifndef ASH_COMMON_TEST_TEST_SHELF_ITEM_DELEGATE_H_
 #define ASH_COMMON_TEST_TEST_SHELF_ITEM_DELEGATE_H_
 
 #include "ash/common/shelf/shelf_item_delegate.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 
 namespace ash {
 
 class WmWindow;
 
 namespace test {
 
 // Test implementation of ShelfItemDelegate.
 class TestShelfItemDelegate : public ShelfItemDelegate {
  public:
   explicit TestShelfItemDelegate(WmWindow* window);
   ~TestShelfItemDelegate() override;
 
   // ShelfItemDelegate:
   ShelfItemDelegate::PerformedAction ItemSelected(
       const ui::Event& event) override;
-  base::string16 GetTitle() override;
   ShelfMenuModel* CreateApplicationMenu(int event_flags) override;
   void Close() override;
 
  private:
   WmWindow* window_;
 
   DISALLOW_COPY_AND_ASSIGN(TestShelfItemDelegate);
 };
 
 }  // namespace test
 }  // namespace ash
 
 #endif  // ASH_COMMON_TEST_TEST_SHELF_ITEM_DELEGATE_H_