Material PDF: Drastically reduce time required to stamp complex bookmark trees

chrome/test/data/pdf/material_elements_test.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.
 
 /**
  * Standalone unit tests of the PDF Polymer elements.
  */
 var tests = [
   /**
    * Test that viewer-page-selector reacts correctly to text entry. The page
@@ skipping 91 matching lines @@
       depth: 1
     });
 
     // Force templates to render.
     Polymer.dom.flush();
 
     var rootBookmarks =
         bookmarkContent.shadowRoot.querySelectorAll('viewer-bookmark');
     chrome.test.assertEq(1, rootBookmarks.length, "one root bookmark");
     var rootBookmark = rootBookmarks[0];
+    MockInteractions.tap(rootBookmark.$.expand);
+
+    Polymer.dom.flush();
 
     var subBookmarks =
         rootBookmark.shadowRoot.querySelectorAll('viewer-bookmark');
     chrome.test.assertEq(2, subBookmarks.length, "two sub bookmarks");
     chrome.test.assertEq(1, subBookmarks[1].depth,
                            "sub bookmark depth correct");
 
     var lastPageChange;
     rootBookmark.addEventListener('change-page', function(e) {
       lastPageChange = e.detail.page;
     });
 
     MockInteractions.tap(rootBookmark.$.item);
     chrome.test.assertEq(1, lastPageChange);
 
     MockInteractions.tap(subBookmarks[1].$.item);
     chrome.test.assertEq(3, lastPageChange);
 
-    var subBookmarkDiv =
-        rootBookmark.shadowRoot.querySelector('.sub-bookmark');
-
-    chrome.test.assertTrue(subBookmarkDiv.hidden);
-    MockInteractions.tap(rootBookmark.$.expand);
-    chrome.test.assertFalse(subBookmarkDiv.hidden);
-    chrome.test.assertEq('hidden', subBookmarks[1].$.expand.style.visibility);
-
     chrome.test.succeed();
   },
 
   /**
    * Test that the zoom toolbar toggles between showing the fit-to-page and
    * fit-to-width buttons.
    */
   function testZoomToolbarToggle() {
     var zoomToolbar = Polymer.Base.create('viewer-zoom-toolbar', {});
     var fitButton = zoomToolbar.$['fit-button'];
@@ skipping 30 matching lines @@
     MockInteractions.tap(fab);
     assertEvent('fit-to-page');
 
     chrome.test.succeed();
   }
 ];
 
 importTestHelpers().then(function() {
   chrome.test.runTests(tests);
 });