Revert "Patch Ember to fix https://github.com/emberjs/ember.js/issues/9805"

This reverts commit 393607d25c.

app/assets/javascripts/discourse/controllers/discovery/topics.js.es6

@@ -158,11 +158,11 @@ var controllerOpts = {
   }.property('allLoaded', 'topics.length'),
 
   footerEducation: function() {
-    if (!this.get('allLoaded') || this.get('topics.length') > 0 || !Discourse.User.current()) { return; }
+    if (!this.get('allLoaded') || this.get('topics.length') > 0 || !Discourse.User.current()) { return ""; }
 
     var split = this.get('filter').split('/');
 
-    if (split[0] !== 'new' && split[0] !== 'unread' && split[0] !== 'starred') { return; }
+    if (split[0] !== 'new' && split[0] !== 'unread' && split[0] !== 'starred') { return ""; }
 
     return I18n.t("topics.none.educate." + split[0], {
       userPrefsUrl: Discourse.getURL("/users/") + (Discourse.User.currentProp("username_lower")) + "/preferences"

app/assets/javascripts/discourse/models/user.js

@@ -92,7 +92,7 @@ Discourse.User = Discourse.Model.extend({
       desc = I18n.t('user.moderator', {user: name});
       return '<i class="fa fa-shield" title="' + desc +  '" alt="' + desc + '"></i>';
     }
-    return null;
+    return "";
   }.property('admin','moderator'),
 
   /**

vendor/assets/javascripts/development/ember.js

@@ -10112,10 +10112,6 @@ enifed("ember-handlebars/string",
       @return {Handlebars.SafeString} a string that will not be html escaped by Handlebars
     */
     function htmlSafe(str) {
-      if (str === undefined || str === null) {
-        return "";
-      }
-
       if (typeof str !== 'string') {
         str = ''+str;
       }

vendor/assets/javascripts/production/ember.js

@@ -9819,10 +9819,6 @@ enifed("ember-handlebars/string",
       @return {Handlebars.SafeString} a string that will not be html escaped by Handlebars
     */
     function htmlSafe(str) {
-      if (str === undefined || str === null) {
-        return "";
-      }
-
       if (typeof str !== 'string') {
         str = ''+str;
       }