Use a split toggle button to reflect scaling state.

remoting/remoting.gyp

 # Copyright (c) 2011 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': {
     # TODO(dmaclach): can we pick this up some other way? Right now it's
     # duplicated from chrome.gyp
     'chromium_code': 1,
     # Use a consistent MIME-type independent of branding.
@@ skipping 62 matching lines @@
       'webapp/me2mom/debug_log.js',
       'webapp/me2mom/dividerbottom.png',
       'webapp/me2mom/dividertop.png',
       'webapp/me2mom/l10n.js',
       'webapp/me2mom/main.css',
       'webapp/me2mom/manifest.json',
       'webapp/me2mom/oauth2.js',
       'webapp/me2mom/oauth2_callback.html',
       'webapp/me2mom/plugin_settings.js',
       'webapp/me2mom/remoting.js',
+      'webapp/me2mom/scale-to-fit.png',
       'webapp/me2mom/spinner.gif',
       'webapp/me2mom/toolbar.css',
       'webapp/me2mom/toolbar-stub.png',
       'webapp/me2mom/xhr.js',
     ],
     'remoting_it2me_locale_files': [
       'webapp/me2mom/_locales/en/messages.json',
     ],
   },
 
@@ skipping 746 matching lines @@
                   '../base/allocator/allocator.gyp:allocator',
                 ],
               },
             ],
           ],
         }],
       ],  # end of 'conditions'
     },  # end of target 'remoting_unittests'
   ],  # end of targets
 }