FIX: Triggering a refresh while subcategory lists was broken.

It would then list all categories isntead of the subcategory you were
viewing at that time.

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

@@ -8,7 +8,6 @@ export default DiscoveryController.extend({
 
   actions: {
     refresh: function() {
-      var self = this;
 
       // Don't refresh if we're still loading
       if (this.get('controllers.discovery.loading')) { return; }
@@ -17,7 +16,17 @@ export default DiscoveryController.extend({
       // router and ember throws an error due to missing `handlerInfos`.
       // Lesson learned: Don't call `loading` yourself.
       this.set('controllers.discovery.loading', true);
-      Discourse.CategoryList.list('categories').then(function(list) {
+
+      var parentCategory = this.get('model.parentCategory');
+      var promise;
+      if (parentCategory) {
+        promise = Discourse.CategoryList.listForParent(parentCategory);
+      } else {
+        promise = Discourse.CategoryList.list();
+      }
+
+      var self = this;
+      promise.then(function(list) {
         self.set('model', list);
         self.send('loadingComplete');
       });

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

@@ -1,11 +1,3 @@
-/**
-  A data model for containing a list of categories
-
-  @class CategoryList
-  @extends Discourse.Model
-  @namespace Discourse
-  @module Discourse
-**/
 Discourse.CategoryList = Ember.ArrayProxy.extend({
   init: function() {
     this.set('content', []);
@@ -50,7 +42,8 @@ Discourse.CategoryList.reopenClass({
     var self = this;
     return Discourse.ajax('/categories.json?parent_category_id=' + category.get('id')).then(function(result) {
       return Discourse.CategoryList.create({
-        categories: self.categoriesFrom(result)
+        categories: self.categoriesFrom(result),
+        parentCategory: category
       });
     });
   },

app/assets/javascripts/discourse/templates/discovery/topics.hbs

@@ -16,7 +16,7 @@
 
 {{#if selected}}
   <div id='bulk-select'>
-    <button class='btn no-text' {{action "showBulkActions"}}><i class="fa fa-wrench"></i></button>
+    {{d-button action="showBulkActions" icon="wrench" class="no-text"}}
   </div>
 {{/if}}