MD History: Implement search functionality.

chrome/browser/resources/md_history/history_card.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.
 
 Polymer({
   is: 'history-card',
 
   properties: {
-    // The date of these history items.
+    // The date associated with the history-card.
     historyDate: {
       type: String,
       value: ''
     },
 
     // The list of history results that were accessed for a particular day in
     // reverse chronological order.
     historyItems: {
       type: Array,
       value: function() { return []; }
+    },
+
+    searchTerm: {
+      type: String,
+      value: ''
     }
   },
 
   /**
    * Check whether the time difference between the given historyItem and the
    * next one is large enough for a spacer to be required.
    * @param {number} index The index number of the first item being compared.
    * @param {number} itemsLength The number of items on the card. Used to force
    * needsTimeGap_ to run for every item if an item is deleted from the card.
+   * @param {string} search The search term associated with this item.
    * @return {boolean} Whether or not time gap separator is required.
    * @private
    */
-  needsTimeGap_: function(index, itemsLength) {
+  needsTimeGap_: function(index, itemsLength, search) {
     var items = this.historyItems;
-    return index + 1 < items.length &&
+
+    if (search == '' || search == undefined) {
+      return index + 1 < items.length &&
         items[index].time - items[index + 1].time > BROWSING_GAP_TIME;
+    } else {
+      return index + 1 < items.length &&
+          items[index].visibleTimestamp != items[index + 1].visibleTimestamp;
+    }
+  },
+
+  /**
+   * Generates the title for this history card.
+   * @param {number} numberOfItems The number of items in the card.
+   * @param {string} search The search term associated with these results.
+   * @private
+   */
+  cardTitle_: function(numberOfItems, search, historyDate) {
+    var resultId = numberOfItems == 1 ? 'searchResult' : 'searchResults';
+
+    if (search == '' || search == undefined) {

[tsergeant, 2016/02/12 00:03:52]

Can search actually ever be undefined?
Can you do
  if (search) {
  }

?

Also, remove these {} or add them back on the else clause as well

(if you have braces at all, you have to have them on every branch)

[hsampson, 2016/02/12 06:45:43]

No I don't think it can.

+      return historyDate;
+    } else
+      return loadTimeData.getStringF('foundSearchResults', numberOfItems,
+                                     loadTimeData.getString(resultId), search);
   }
 });