[MD History] Copy stats from the old history page.

chrome/browser/resources/md_history/app.js

 // Copyright 2016 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-app',
 
   properties: {
     showSidebarFooter: Boolean,
 
@@ skipping 183 matching lines @@
     }
   },
 
   /**
    * @param {string} searchTerm
    * @private
    */
   searchTermChanged_: function(searchTerm) {
     this.set('queryParams_.q', searchTerm || null);
     this.$['history'].queryHistory(false);
+    // TODO(tsergeant): Ignore incremental searches in this metric.
+    if (this.queryState_.searchTerm)
+      md_history.BrowserService.getInstance().recordAction('Search');
   },
 
   /**
    * @param {string} searchQuery
    * @private
    */
   searchQueryParamChanged_: function(searchQuery) {
     this.$.toolbar.setSearchTerm(searchQuery || '');
   },
 
@@ skipping 118 matching lines @@
             break;
         }
         break;
     }
 
     md_history.BrowserService.getInstance().recordHistogram(
       'History.HistoryView', histogramValue, HistoryViewHistogram.END
     );
   },
 });