[AppRemoting] Break out AppRemoting shared module (re-land).

remoting/app_remoting_webapp.gyp

 # 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.
 
 {
   'includes': [
     '../remoting/remoting_locales.gypi',
     '../remoting/app_remoting_webapp_build.gypi',
   ],
 
@@ skipping 27 matching lines @@
             ],
             'action': [
               'python', '../third_party/closure_compiler/compile.py',
               '<@(compiler_flags)',
               '--success-stamp', '<(success_stamp)',
               '<@(ar_main_js_files)',
               '<@(remoting_webapp_js_proto_files)',
             ],
           },
           {
-            'action_name': 'Verify >(ar_app_name) background.js',
+            'action_name': 'Verify >(ar_app_name) background.html',
             'variables': {
               'success_stamp': '<(PRODUCT_DIR)/>(_target_name)_background_jscompile.stamp',
             },
             'inputs': [
-              '<@(ar_background_js_files)',
+              '<@(ar_background_html_js_files)',
               '<@(remoting_webapp_js_proto_files)',
               # Include zip as input so that this action is run after the build.
               '<(zip_path)',
             ],
             'outputs': [
               '<(success_stamp)',
             ],
             'action': [
               'python', '../third_party/closure_compiler/compile.py',
               '<@(compiler_flags)',
               '--success-stamp', '<(success_stamp)',
-              '<@(ar_background_js_files)',
+              '<@(ar_background_html_js_files)',
               '<@(remoting_webapp_js_proto_files)',
             ],
           },
           {
             'action_name': 'Verify >(ar_app_name) feedback_consent.html',
             'variables': {
               'success_stamp': '<(PRODUCT_DIR)/>(_target_name)_feedback_consent_jscompile.stamp',
             },
             'inputs': [
               '<@(ar_feedback_consent_html_all_js_files)',
@@ skipping 25 matching lines @@
       'app_key': 'Sample_App',
       'app_id': 'ljacajndfccfgnfohlgkdphmbnpkjflk',
       'app_client_id': 'sample_client_id',
       'app_name': 'App Remoting Client',
       'app_description': 'App Remoting client',
       'app_capabilities': ['GOOGLE_DRIVE'],
       'manifest_key': 'remotingdevbuild',
     },
   ],  # end of targets
 }