MD Settings: Prevent <settings-prefs> from being initialized in guest mode.

chrome/browser/resources/settings/settings_ui/settings_ui.js

Index: chrome/browser/resources/settings/settings_ui/settings_ui.js
diff --git a/chrome/browser/resources/settings/settings_ui/settings_ui.js b/chrome/browser/resources/settings/settings_ui/settings_ui.js
index 59d21d3c3255ef5b292e9085314a9aa3d34ac05c..47ad3a7b4feffc86491981afb8f5566e8d710056 100644
--- a/chrome/browser/resources/settings/settings_ui/settings_ui.js
+++ b/chrome/browser/resources/settings/settings_ui/settings_ui.js
@@ -25,6 +25,12 @@ Polymer({
      */
     prefs: Object,
 
+    /** @private */
+    isGuestMode_: {
+      type: Boolean,
+      value: loadTimeData.getBoolean('isGuest'),
+    },
+
     /** @type {?settings.DirectionDelegate} */
     directionDelegate: {
       observer: 'directionDelegateChanged_',
@@ -70,7 +76,7 @@ Polymer({
       drawer.close();
     }.bind(this));
 
-    if (loadTimeData.getBoolean('isGuest')) {
+    if (this.isGuestMode_) {
       this.pageVisibility_ = {
         people: false,
         onStartup: false,