Add unit-tests for MenuButton and simplify implementation.

remoting/remoting_webapp_files.gypi

 # 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.
 
 {
   'variables': {
     'remoting_webapp_info_files': [
       'resources/chromoting16.webp',
       'resources/chromoting48.webp',
       'resources/chromoting128.webp',
@@ skipping 118 matching lines @@
     ],
     # These product files are excluded from our JavaScript unittest
     'remoting_webapp_unittest_exclude_files': [
       # event_handlers.js is where the onLoad handler is defined, which
       # makes it the entry point of the webapp.
       'webapp/event_handlers.js',
     ],
     # The unit test cases for the webapp
     'remoting_webapp_unittest_cases': [
       'webapp/unittests/test_eventSource.js',
+      'webapp/unittests/menu_button_unittest.js',
+    ],
+    'remoting_webapp_unittest_additional_files': [
+      'webapp/menu_button.css',
     ],
     'remoting_webapp_unittest_template_main':
       'webapp/html/template_unittest.html',
 
     # The JavaScript files required by main.html.
     'remoting_webapp_main_html_js_files': [
       # Include the core files first as it is required by the other files.
       # Otherwise, Jscompile will complain.
       '<@(remoting_webapp_js_core_files)',
       '<@(remoting_webapp_js_auth_client2host_files)',
@@ skipping 93 matching lines @@
       'webapp/html/dialog_token_refresh_failed.html',
       'webapp/html/toolbar.html',
       'webapp/html/ui_header.html',
       'webapp/html/ui_it2me.html',
       'webapp/html/ui_me2me.html',
       'webapp/html/window_frame.html',
     ],
 
   },
 }