WidgetDelegateView is its own contents view.

mash/webtest/webtest.cc

 // Copyright 2016 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 "mash/webtest/webtest.h"
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string16.h"
@@ skipping 41 matching lines @@
   ~UI() override {
     webtest_->RemoveWindow(GetWidget());
   }
 
   void NavigateTo(const GURL& url) {
     view_->NavigateTo(url);
   }
 
  private:
   // Overridden from views::WidgetDelegate:
-  views::View* GetContentsView() override { return this; }
   base::string16 GetWindowTitle() const override {
     // TODO(beng): use resources.
     if (current_title_.empty())
       return base::ASCIIToUTF16("navigation::View client");
     base::string16 format = base::ASCIIToUTF16("%s - navigation::View client");
     base::ReplaceFirstSubstringAfterOffset(
         &format, 0, base::ASCIIToUTF16("%s"), current_title_);
     return format;
   }
   bool CanResize() const override { return true; }
@@ skipping 122 matching lines @@
   AddWindow(window);
 }
 
 void Webtest::Create(const shell::Identity& remote_identity,
                      mojom::LaunchableRequest request) {
   bindings_.AddBinding(this, std::move(request));
 }
 
 }  // namespace webtest
 }  // namespace mash