MD Settings: Hide the advanced page toggle control during searching.

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;
+
+/**
  * @fileoverview
  * 'settings-main' displays the selected settings page.
  */
 Polymer({
   is: 'settings-main',
 
   behaviors: [settings.RouteObserverBehavior],
 
   properties: {
     /**
@@ skipping 14 matching lines @@
     inSubpage_: Boolean,
 
     /** @private */
     overscroll_: {
       type: Number,
       observer: 'overscrollChanged_',
     },
 
     /**
      * Controls which main pages are displayed via dom-ifs.
-     * @type {!{about: boolean, basic: boolean, advanced: boolean}}
-     * @private
+     * @private {!MainPageVisibility}
      */
     showPages_: {
       type: Object,
       value: function() {
         return {about: false, basic: false, advanced: false};
       },
     },
 
+    /**
+     * The main pages that were displayed before search was initiated. When
+     * |null| it indicates that currently the page is displaying its normal
+     * contents, instead of displaying search results.
+     * @private {?MainPageVisibility}
+     */
+    previousShowPages_: {
+      type: Object,
+      value: null,
+    },
+
     /** @private */
     showNoResultsFound_: {
       type: Boolean,
       value: false,
     },
 
     toolbarSpinnerActive: {
       type: Boolean,
       value: false,
       notify: true,
@@ skipping 45 matching lines @@
   /**
    * @param {boolean} opened Whether the menu is expanded.
    * @return {string} Which icon to use.
    * @private
    */
   arrowState_: function(opened) {
     return opened ? 'settings:arrow-drop-up' : 'cr:arrow-drop-down';
   },
 
   /**
-   * @param {boolean} showBasicPage
-   * @param {boolean} inSubpage
    * @return {boolean}
    * @private
    */
-  showAdvancedToggle_: function(showBasicPage, inSubpage) {
-    return showBasicPage && !inSubpage;
+  showAdvancedToggle_: function() {
+    var inSearchMode = !!this.previousShowPages_;
+    return this.showPages_.basic && !this.inSubpage_ && !inSearchMode;
   },
 
   /** @protected */
   currentRouteChanged: function(newRoute) {
     this.inSubpage_ = newRoute.subpage.length > 0;
     this.style.height = this.inSubpage_ ? '100%' : '';
 
     if (settings.Route.ABOUT.contains(newRoute)) {
       this.showPages_ = {about: true, basic: false, advanced: false};
     } else {
@@ skipping 59 matching lines @@
    */
   ensureInDefaultSearchPage_: function() {
     settings.navigateTo(settings.Route.BASIC);
   },
 
   /**
    * @param {string} query
    * @return {!Promise} A promise indicating that searching finished.
    */
   searchContents: function(query) {
+    if (!this.previousShowPages_) {
+      // Store which pages are shown before search, so that they can be restored
+      // after the user clears the search results.
+      this.previousShowPages_ = this.showPages_;
+    }
+
     this.ensureInDefaultSearchPage_();
     this.toolbarSpinnerActive = true;
 
     // Trigger rendering of the basic and advanced pages and search once ready.
     this.showPages_ = {about: false, basic: true, advanced: true};
 
     return new Promise(function(resolve, reject) {
       setTimeout(function() {
         var whenSearchDone = settings.getSearchManager().search(
             query, assert(this.$$('settings-basic-page')));
         assert(
             whenSearchDone ===
                 settings.getSearchManager().search(
                     query, assert(this.$$('settings-advanced-page'))));
 
         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;
+          var showingSearchResults = !request.isSame('');
           this.showNoResultsFound_ =
-              !request.isSame('') && !request.didFindMatches();
+              showingSearchResults && !request.didFindMatches();
+
+          if (!showingSearchResults) {
+            // Restore the pages that were shown before search was initiated.
+            this.showPages_ = assert(this.previousShowPages_);
+            this.previousShowPages_ = null;
+          }
         }.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;
   },
 });