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

remoting/webapp/app_remoting/vendor/arv_main.js

Index: remoting/webapp/app_remoting/vendor/arv_main.js
diff --git a/remoting/webapp/app_remoting/js/ar_main.js b/remoting/webapp/app_remoting/vendor/arv_main.js
similarity index 57%
rename from remoting/webapp/app_remoting/js/ar_main.js
rename to remoting/webapp/app_remoting/vendor/arv_main.js
index 2efe129e03ce323801c0e9814573cfe78edae02f..0278bf82ef47a1ab3426b05744ce38f26f4ac904 100644
--- a/remoting/webapp/app_remoting/js/ar_main.js
+++ b/remoting/webapp/app_remoting/vendor/arv_main.js
@@ -11,7 +11,14 @@ var remoting = remoting || {};
  * Entry point ('load' handler) for App Remoting webapp.
  */
 remoting.startAppRemoting = function() {
-  remoting.app = new remoting.AppRemoting(remoting.app_capabilities());
+  // This string is overwritten with the actual app id by the build script.
+  var appId = 'APP_REMOTING_APPLICATION_ID';
+
+  // This string is overwritten with the actual capabilities required by
+  // this application.
+  var capabilities = ['APPLICATION_CAPABILITIES'];
+
+  remoting.app = new remoting.AppRemoting(appId, capabilities);
   remoting.app.start();
 };