added eventhub to emit update tokens event

app/assets/javascripts/boards/boards_bundle.js

@@ -3,6 +3,7 @@
 /* global BoardService */
 
 import FilteredSearchBoards from './filtered_search_boards';
+import eventHub from './eventhub';
 
 window.Vue = require('vue');
 window.Vue.use(require('vue-resource'));
@@ -78,10 +79,10 @@ $(() => {
       this.filterManager = new FilteredSearchBoards(Store.filter, true, [(this.milestoneTitle ? 'milestone' : null)]);
 
       // Listen for updateTokens event
-      this.$on('updateTokens', this.updateTokens);
+      eventHub.$on('updateTokens', this.updateTokens);
     },
     beforeDestroy() {
-      this.$off('updateTokens', this.updateTokens);
+      eventHub.$off('updateTokens', this.updateTokens);
     },
     mounted () {
       Store.disabled = this.disabled;

app/assets/javascripts/boards/components/issue_card_inner.js

 /* global Vue */
+import eventHub from '../eventhub';
+
 (() => {
   const Store = gl.issueBoards.BoardsStore;
 
@@ -54,7 +56,7 @@
 
         Store.updateFiltersUrl();
 
-        gl.IssueBoardsApp.$emit('updateTokens');
+        eventHub.$emit('updateTokens');
       },
       labelStyle(label) {
         return {

app/assets/javascripts/boards/eventhub.js

+import Vue from 'vue';
+
+export default new Vue();