MD User Manager: Fixes flaky tests

chrome/test/data/webui/md_user_manager/user_manager_pages_tests.js

Index: chrome/test/data/webui/md_user_manager/user_manager_pages_tests.js
diff --git a/chrome/test/data/webui/md_user_manager/user_manager_pages_tests.js b/chrome/test/data/webui/md_user_manager/user_manager_pages_tests.js
index 9a32094b8004bb2ce5742389f0cc397f7fb2a2a9..19a809e21baddf65297864283747eb825ac6a265 100644
--- a/chrome/test/data/webui/md_user_manager/user_manager_pages_tests.js
+++ b/chrome/test/data/webui/md_user_manager/user_manager_pages_tests.js
@@ -9,12 +9,15 @@ cr.define('user_manager.user_manager_pages_tests', function() {
       var pagesElement = null;
 
       setup(function() {
-        PolymerTest.clearBody();
         pagesElement = document.createElement('user-manager-pages');
         document.body.appendChild(pagesElement);
       });
 
-      teardown(function() { pagesElement.remove(); });
+      teardown(function(done) {
+        pagesElement.remove();
+        // Allow asynchronous tasks to finish.
+        setTimeout(done);
+      });
 
       test('User Pods page is the default visible page', function() {
         assertTrue(