Add custom Polymer network icon element

chrome/browser/resources/chromeos/network_ui/compiled_resources.gyp

 # Copyright 2015 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.
 {
   'targets': [
     {
       'target_name': 'network_ui',
 
       'variables': {
         'depends': [
           '../../../../../ui/webui/resources/js/compiled_resources.gyp:util',
           '../../../../../ui/webui/resources/js/compiled_resources.gyp:load_time_data',
         ],
         'externs': [
+          '../../../../../ui/webui/resources/cr_elements/cr_onc/cr-onc-types.js',
           '../../../../../third_party/closure_compiler/externs/chrome_extensions.js'
         ],
       },
       'includes': ['../../../../../third_party/closure_compiler/compile_js.gypi'],
     },
   ],
 }