Fixes many Ember 1.9.0 deprecations

app/assets/javascripts/admin/models/site_setting.js

@@ -9,16 +9,13 @@ Discourse.SiteSetting = Discourse.Model.extend({
   **/
   enabled: function(key, value) {
 
-    if (arguments.length === 1) {
-      // get the boolean value of the setting
-      if (this.blank('value')) return false;
-      return this.get('value') === 'true';
-
-    } else {
-      // set the boolean value of the setting
+    if (arguments.length > 1) {
       this.set('value', value ? 'true' : 'false');
     }
 
+    if (this.blank('value')) return false;
+    return this.get('value') === 'true';
+
   }.property('value'),
 
   /**

app/assets/javascripts/admin/models/user-field.js.es6

@@ -1,8 +1,3 @@
-var _fieldTypes = [
-      Ember.Object.create({id: 'text', name: I18n.t('admin.user_fields.field_types.text') }),
-      Ember.Object.create({id: 'confirm', name: I18n.t('admin.user_fields.field_types.confirm') })
-    ];
-
 var UserField = Ember.Object.extend({
   destroy: function() {
     var self = this;
@@ -43,11 +38,18 @@ UserField.reopenClass({
   },
 
   fieldTypes: function() {
-    return _fieldTypes;
+    if (!this._fieldTypes) {
+      this._fieldTypes = [
+        Ember.Object.create({id: 'text', name: I18n.t('admin.user_fields.field_types.text') }),
+        Ember.Object.create({id: 'confirm', name: I18n.t('admin.user_fields.field_types.confirm') })
+      ];
+    }
+
+    return this._fieldTypes;
   },
 
   fieldTypeById: function(id) {
-    return _fieldTypes.findBy('id', id);
+    return this.fieldTypes().findBy('id', id);
   }
 });