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

chrome/browser/resources/history/history.js

Index: chrome/browser/resources/history/history.js
diff --git a/chrome/browser/resources/history/history.js b/chrome/browser/resources/history/history.js
index 1227c99fe478fdc36b50399cc090c380ed4d447a..4ef1b84955ee177c8c873abfa10142e76ef3d81a 100644
--- a/chrome/browser/resources/history/history.js
+++ b/chrome/browser/resources/history/history.js
@@ -938,6 +938,13 @@ HistoryView.prototype.onModelReady = function(doneLoading) {
     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);
+  }
 };
 
 /**
@@ -1298,7 +1305,6 @@ HistoryView.prototype.displayResults_ = function(doneLoading) {
           createElementWithClassName('div', 'no-results-message'));
       noResults.textContent = loadTimeData.getString('noResults');
       this.resultDiv_.appendChild(resultsFragment);
-      this.updateNavBar_();
       return;
     }
 
@@ -1326,7 +1332,6 @@ HistoryView.prototype.displayResults_ = function(doneLoading) {
     // Add all the days and their visits to the page.
     this.resultDiv_.appendChild(resultsFragment);
   }
-  this.updateNavBar_();
 };
 
 /**
@@ -1335,9 +1340,10 @@ HistoryView.prototype.displayResults_ = function(doneLoading) {
  */
 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 =