MD Settings search code will not assume the Advanced section exists.

chrome/browser/resources/settings/settings_main/settings_main.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @typedef {{about: boolean, basic: boolean, advanced: boolean}}
  */
 var MainPageVisibility;
 
 /**
@@ skipping 312 matching lines @@
    */
   searchContents: function(query) {
     // Trigger rendering of the basic and advanced pages and search once ready.
     this.inSearchMode_ = true;
     this.toolbarSpinnerActive = true;
 
     return new Promise(function(resolve, reject) {
       setTimeout(function() {
         var whenSearchDone = settings.getSearchManager().search(
             query, assert(this.getPage_(settings.Route.BASIC)));
-        assert(
-            whenSearchDone ===
-                settings.getSearchManager().search(
-                    query, assert(this.getPage_(settings.Route.ADVANCED))));
+
+        if (this.pageVisibility.advancedSettings !== false) {
+          assert(whenSearchDone === settings.getSearchManager().search(
+              query, assert(this.getPage_(settings.Route.ADVANCED))));
+        }
 
         whenSearchDone.then(function(request) {
           resolve();
           if (!request.finished) {
             // Nothing to do here. A previous search request was canceled
             // because a new search request was issued before the first one
             // completed.
             return;
           }
 
           this.toolbarSpinnerActive = false;
           this.inSearchMode_ = !request.isSame('');
           this.showNoResultsFound_ =
               this.inSearchMode_ && !request.didFindMatches();
         }.bind(this));
       }.bind(this), 0);
     }.bind(this));
   },
 
   /**
    * @param {(boolean|undefined)} visibility
    * @return {boolean} True unless visibility is false.
    * @private
    */
   showAdvancedSettings_: function(visibility) {
     return visibility !== false;
   },
 });