Remove unnecessary computed property.

app/assets/javascripts/discourse/components/search-advanced-options.js.es6

@@ -388,11 +388,6 @@ export default Em.Component.extend({
     return (this.get('isExpanded')) ? "fa-caret-down" : "fa-caret-right";
   }.property('isExpanded'),
 
-  @computed('isExpanded')
-  isCollapsed(isExpanded){
-    return !isExpanded;
-  },
-
   actions: {
     expandOptions() {
       this.set('isExpanded', !this.get('isExpanded'));

app/assets/javascripts/discourse/templates/components/search-advanced-options.hbs

@@ -1,7 +1,7 @@
 <h3 class="panel-title" {{action "expandOptions"}}>
   <i class="fa {{collapsedClassName}}"></i> {{i18n "search.advanced.title"}}
 </h3>
-{{#unless isCollapsed}}
+{{#if isExpanded}}
   <div class="search-options">
     <div class="container">
       <div class="control-group pull-left">
@@ -77,4 +77,4 @@
       </div>
     </div>
   </div>
-{{/unless}}
+{{/if}}