cros: Bind hangup red button on remote controller to close web dialog

chrome/browser/chromeos/login/ui/login_web_dialog.cc

 // 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.
 
 #include "chrome/browser/chromeos/login/ui/login_web_dialog.h"
 
 #include <deque>
 
 #include "base/lazy_instance.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 152 matching lines @@
   // fire an auto-reload, which in turn leads to opening a new browser window,
   // so we must suppress it.
   // http://crbug.com/443096
   return (source && !chrome::FindBrowserWithWebContents(source));
 }
 
 bool LoginWebDialog::HandleShouldCreateWebContents() {
   return false;
 }
 
+bool LoginWebDialog::AdditionalAccelerator(
+    const ui::Accelerator& accelerator) const {
+  return accelerator.key_code() == ui::VKEY_BROWSER_BACK &&
+         accelerator.IsShiftDown();
+}
+
 }  // namespace chromeos