WidgetDelegateView is its own contents view.

extensions/components/native_app_window/native_app_window_views.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 EXTENSIONS_COMPONENTS_NATIVE_APP_WINDOW_NATIVE_APP_WINDOW_VIEWS_H_
 #define EXTENSIONS_COMPONENTS_NATIVE_APP_WINDOW_NATIVE_APP_WINDOW_VIEWS_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 94 matching lines @@
   bool CanMaximize() const override;
   bool CanMinimize() const override;
   base::string16 GetWindowTitle() const override;
   bool ShouldShowWindowTitle() const override;
   bool ShouldShowWindowIcon() const override;
   void SaveWindowPlacement(const gfx::Rect& bounds,
                            ui::WindowShowState show_state) override;
   void DeleteDelegate() override;
   views::Widget* GetWidget() override;
   const views::Widget* GetWidget() const override;
-  views::View* GetContentsView() override;
   bool ShouldDescendIntoChildForEventHandling(
       gfx::NativeView child,
       const gfx::Point& location) override;
 
   // WidgetObserver implementation.
   void OnWidgetDestroying(views::Widget* widget) override;
   void OnWidgetVisibilityChanged(views::Widget* widget, bool visible) override;
   void OnWidgetActivationChanged(views::Widget* widget, bool active) override;
 
   // WebContentsObserver implementation.
@@ skipping 58 matching lines @@
   views::UnhandledKeyboardEventHandler unhandled_keyboard_event_handler_;
 
   base::ObserverList<web_modal::ModalDialogHostObserver> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeAppWindowViews);
 };
 
 }  // namespace native_app_window
 
 #endif  // EXTENSIONS_COMPONENTS_NATIVE_APP_WINDOW_NATIVE_APP_WINDOW_VIEWS_H_