athena: Introduce ActivityView.

athena/activity/activity_widget_delegate.h

 // Copyright 2014 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 ATHENA_ACTIVITY_ACTIVITY_WIDGET_DELEGATE_H_
 #define ATHENA_ACTIVITY_ACTIVITY_WIDGET_DELEGATE_H_
 
 #include "base/macros.h"
 #include "ui/views/widget/widget_delegate.h"
 
 namespace athena {
 class ActivityViewModel;
 
 // A default WidgetDelegate for activities.
 // TODO(oshima): Allow AcitivyViewModel to create custom WidgetDelegate.
 class ActivityWidgetDelegate : public views::WidgetDelegate {
  public:
   explicit ActivityWidgetDelegate(ActivityViewModel* view_model);
   ~ActivityWidgetDelegate() override;
 
   // views::WidgetDelegate:
   bool CanResize() const override;
   bool CanMaximize() const override;
   bool CanMinimize() const override;
   base::string16 GetWindowTitle() const override;
   void DeleteDelegate() override;
   views::Widget* GetWidget() override;
   const views::Widget* GetWidget() const override;
   views::View* GetContentsView() override;
-  views::ClientView* CreateClientView(views::Widget* widget) override;
   views::NonClientFrameView* CreateNonClientFrameView(
       views::Widget* widget) override;
 
  private:
   ActivityViewModel* view_model_;
 
   DISALLOW_COPY_AND_ASSIGN(ActivityWidgetDelegate);
 };
 
 }  // namespace athena
 
 #endif  // ATHENA_ACTIVITY_ACTIVITY_WIDGET_DELEGATE_H_