Update ConstrainedWindowViews appearance according to mock

chrome/browser/ui/constrained_window_tab_helper_delegate.cc

 // Copyright (c) 2012 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 "chrome/browser/ui/constrained_window_tab_helper_delegate.h"
 
 void ConstrainedWindowTabHelperDelegate::WillShowConstrainedWindow(
     TabContents* source) {
 }
 
 bool ConstrainedWindowTabHelperDelegate::ShouldFocusConstrainedWindow() {
   return true;
 }
 
 void ConstrainedWindowTabHelperDelegate::SetTabContentBlocked(
     TabContents* tab_contents, bool blocked) {
 }
 
 ConstrainedWindowTabHelperDelegate::~ConstrainedWindowTabHelperDelegate() {}
+
+BrowserWindow* ConstrainedWindowTabHelperDelegate::GetBrowserWindow()
+{
+  return NULL;
+}