History: Prevent search box from disappearing when search term is deleted.

chrome/browser/resources/history/history.js

 // Copyright (c) 2012 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.
 
 <include src="../uber/uber_utils.js">
 <include src="history_focus_manager.js">
 
 ///////////////////////////////////////////////////////////////////////////////
 // Globals:
 /** @const */ var RESULTS_PER_PAGE = 150;
@@ skipping 920 matching lines @@
   this.displayResults_(doneLoading);
 
   // Allow custom styling based on whether there are any results on the page.
   // To make this easier, add a class to the body if there are any results.
   if (this.model_.visits_.length)
     document.body.classList.add('has-results');
   else
     document.body.classList.remove('has-results');
 
   this.updateNavBar_();
+
+  if (isMobileVersion()) {
+    // Hide the search field if it is empty and there are no results.
+    var hasResults = this.model_.visits_.length > 0;
+    var isSearch = this.model_.getSearchText().length > 0;
+    $('search-field').hidden = !(hasResults || isSearch);
+  }
 };
 
 /**
  * Enables or disables the buttons that control editing entries depending on
  * whether there are any checked boxes.
  */
 HistoryView.prototype.updateSelectionEditButtons = function() {
   if (loadTimeData.getBoolean('allowDeletingHistory')) {
     var anyChecked = document.querySelector('.entry input:checked') != null;
     $('remove-selected').disabled = !anyChecked;
@@ skipping 340 matching lines @@
   } else {
     var resultsFragment = document.createDocumentFragment();
 
     this.addTimeframeInterval_(resultsFragment);
 
     if (results.length == 0 && doneLoading) {
       var noResults = resultsFragment.appendChild(
           createElementWithClassName('div', 'no-results-message'));
       noResults.textContent = loadTimeData.getString('noResults');
       this.resultDiv_.appendChild(resultsFragment);
-      this.updateNavBar_();
       return;
     }
 
     if (this.getRangeInDays() == HistoryModel.Range.MONTH &&
         groupByDomain) {
       // Group everything together in the month view.
       this.addMonthResults_(results, resultsFragment);
     } else {
       var dayStart = 0;
       var dayEnd = 0;
       // Go through all of the visits and process them in chunks of one day.
       while (dayEnd < results.length) {
         // Skip over the ones that are already rendered.
         while (dayStart < results.length && results[dayStart].isRendered)
           ++dayStart;
         var dayEnd = dayStart + 1;
         while (dayEnd < results.length && results[dayEnd].continued)
           ++dayEnd;
 
         this.addDayResults_(
             results.slice(dayStart, dayEnd), resultsFragment, groupByDomain);
       }
     }
 
     // Add all the days and their visits to the page.
     this.resultDiv_.appendChild(resultsFragment);
   }
-  this.updateNavBar_();
 };
 
 /**
  * Update the visibility of the page navigation buttons.
  * @private
  */
 HistoryView.prototype.updateNavBar_ = function() {
   this.updateRangeButtons_();
+
+  // Managed users have the control bar on top, don't show it on the bottom
+  // as well.
   if (!loadTimeData.getBoolean('isManagedProfile')) {
-    // Managed users have the control bar on top, don't show it on the bottom
-    // as well.
     $('newest-button').hidden = this.pageIndex_ == 0;
     $('newer-button').hidden = this.pageIndex_ == 0;
     $('older-button').hidden =
         this.model_.rangeInDays_ != HistoryModel.Range.ALL_TIME ||
         !this.model_.hasMoreResults();
   }
 };
 
 /**
  * Updates the visibility of the 'Clear browsing data' button.
@@ skipping 593 matching lines @@
     historyView.reload();
 }
 
 // Add handlers to HTML elements.
 document.addEventListener('DOMContentLoaded', load);
 
 // This event lets us enable and disable menu items before the menu is shown.
 document.addEventListener('canExecute', function(e) {
   e.canExecute = true;
 });