MD History: Lazily load element files which are not needed for first paint

chrome/test/data/webui/md_history/history_grouped_list_test.js

Index: chrome/test/data/webui/md_history/history_grouped_list_test.js
diff --git a/chrome/test/data/webui/md_history/history_grouped_list_test.js b/chrome/test/data/webui/md_history/history_grouped_list_test.js
index 8eb7b9285137bc8fbf4c22213127b97b9fb88e4a..434a8c079c42cb81fc31227475994fc46f6691a2 100644
--- a/chrome/test/data/webui/md_history/history_grouped_list_test.js
+++ b/chrome/test/data/webui/md_history/history_grouped_list_test.js
@@ -16,13 +16,6 @@ cr.define('md_history.history_grouped_list_test', function() {
       var PER_MONTH_RESULTS;
 
       suiteSetup(function() {
-        app = $('history-app');
-        app.grouped_ = true;
-
-        listContainer = app.$['history'];
-        toolbar = app.$['toolbar'];
-        sidebar = app.$['content-side-bar'];
-
         SIMPLE_RESULTS = [
           createHistoryEntry('2016-03-16', 'https://www.google.com/'),
           createHistoryEntry('2016-03-16', 'https://en.wikipedia.org/DankMeme'),
@@ -46,7 +39,15 @@ cr.define('md_history.history_grouped_list_test', function() {
           createHistoryEntry('2016-03-1', 'https://en.wikipedia.org'),
           createHistoryEntry('2016-03-1', 'https://en.wikipedia.org')
         ];
+      });
 
+      setup(function() {
+        app = replaceApp();
+        app.grouped_ = true;
+
+        listContainer = app.$['history'];
+        toolbar = app.$['toolbar'];
+        sidebar = app.$['content-side-bar'];
         return flush().then(function() {
           groupedList = app.$.history.$$('#grouped-list');
           assertTrue(!!groupedList);
@@ -305,12 +306,6 @@ cr.define('md_history.history_grouped_list_test', function() {
             JSON.stringify(expected),
             JSON.stringify(groupedList.buildRemovalTree_(paths)));
       });
-
-      teardown(function() {
-        app.unselectAll();
-        app.set('queryState_.results', []);
-        app.set('queryState_.searchedTerm', '');
-      });
     });
   }
   return {