move title computed property back to nav-item so it can be overriden in a plugin

app/assets/javascripts/discourse/components/navigation-item.js.es6

@@ -4,22 +4,10 @@ import { bufferedRender } from 'discourse-common/lib/buffered-render';
 export default Ember.Component.extend(bufferedRender({
   tagName: 'li',
   classNameBindings: ['active', 'content.hasIcon:has-icon'],
-  attributeBindings: ['title'],
+  attributeBindings: ['content.title:title'],
   hidden: Em.computed.not('content.visible'),
   rerenderTriggers: ['content.count'],
 
-  @computed("content.categoryName", "content.name")
-  title(categoryName, name) {
-    const extra = {};
-
-    if (categoryName) {
-      name = "category";
-      extra.categoryName = categoryName;
-    }
-
-    return I18n.t("filters." + name.replace("/", ".") + ".help", extra);
-  },
-
   @computed("content.filterMode", "filterMode")
   active(contentFilterMode, filterMode) {
     return contentFilterMode === filterMode ||

app/assets/javascripts/discourse/models/nav-item.js.es6

@@ -3,6 +3,18 @@ import computed from 'ember-addons/ember-computed-decorators';
 
 const NavItem = Discourse.Model.extend({
 
+  @computed("categoryName", "name")
+  title(categoryName, name) {
+    const extra = {};
+
+    if (categoryName) {
+      name = "category";
+      extra.categoryName = categoryName;
+    }
+
+    return I18n.t("filters." + name.replace("/", ".") + ".help", extra);
+  },
+
   @computed("categoryName", "name", "count")
   displayName(categoryName, name, count) {
     count = count || 0;