simplify getting token communication

app/assets/javascripts/user/app/app.js.coffee

@@ -17,21 +17,13 @@
     # $('body').append frame
     # window.location = "#{$obtain_token_url}"
     auth_win = window.open $obtain_token_url, "_blank", "location=no"
-    auth_win.addEventListener "loadstop", ->
-      # auth_win.executeScript(code: "localStorage.setItem( 'name', '' );")
-      watch_loop = setInterval ->
-        auth_win.executeScript {code: "localStorage.getItem( 'auth_token' )"}, (values)->
-          token = values[0]
-          if token
-            clearInterval( watch_loop )
-            auth_win.executeScript {code: "localStorage.setItem('auth_token', '');"}
-            auth_win.executeScript {code: "localStorage.getItem( 'user_id' )"}, (user_id_values)->
-              user_id = user_id_values[0]
-              Qstorage.setItem 'user_id', user_id
-              Qstorage.setItem 'auth_token', token
-            auth_win.close()
-      , 200
-
+    auth_win.addEventListener "loadstart", (event)->
+      if event.url.match 'close_window'
+        user_id = event.url.match(/user_id=([\w+-]+)/)[1]
+        auth_token = event.url.match(/auth_token=([\w-]+)/)[1]
+        Qstorage.setItem 'user_id', user_id
+        Qstorage.setItem 'auth_token', token
+        auth_win.close()
 
 Ember.$.ajaxPrefilter (options) ->
   if options.type.toUpperCase() == 'GET'