[MD settings] keep drawer open when toggling advanced page

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 a6b1008786877c440740f457859cfd2ace456965..1275cf1740d3da50eae57e49394f9e9f97750f51 100644
--- a/chrome/browser/resources/settings/settings_ui/settings_ui.js
+++ b/chrome/browser/resources/settings/settings_ui/settings_ui.js
@@ -31,9 +31,13 @@ Polymer({
     'sideNav.iron-activate': 'onIronActivate_',
   },
 
-  /** @private */
-  onIronActivate_: function() {
-    this.$$('app-drawer').close();
+  /**
+   * @param {Event} event
+   * @private
+   */
+  onIronActivate_: function(event) {
+    if (event.detail.item.id != 'advancedPage')
+      this.$$('app-drawer').close();
   },
 
   /** @private */