Improve syncing between dom distiller and the print preview request

components/dom_distiller/core/javascript/dom_distiller_viewer.js

 // Copyright 2014 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.
 
 // This variable will be changed by iOS scripts.
 var distiller_on_ios = false;
 
 function addToPage(html) {
   var div = document.createElement('div');
   div.innerHTML = html;
   document.getElementById('content').appendChild(div);
   fillYouTubePlaceholders();
-
-  if (typeof navigate_on_initial_content_load !== 'undefined' &&
-      navigate_on_initial_content_load) {
-    navigate_on_initial_content_load = false;
-    setTimeout(function() {
-        window.location = window.location + "#loaded";
-    }, 0);
-  }
 }
 
 function fillYouTubePlaceholders() {
   var placeholders = document.getElementsByClassName('embed-placeholder');
   for (var i = 0; i < placeholders.length; i++) {
     if (!placeholders[i].hasAttribute('data-type') ||
         placeholders[i].getAttribute('data-type') != 'youtube' ||
         !placeholders[i].hasAttribute('data-id')) {
       continue;
     }
@@ skipping 10 matching lines @@
     container.setAttribute('class', 'youtubeContainer');
     container.appendChild(embed);
 
     parent.replaceChild(container, placeholders[i]);
   }
 }
 
 function showLoadingIndicator(isLastPage) {
   document.getElementById('loadingIndicator').className =
       isLastPage ? 'hidden' : 'visible';
+  // This function will be one of the last things to occur when a page is
+  // loaded. This is temporarily used to signal print preview to generate
+  // a PDF.
+  if (isLastPage) {
+    setTimeout(function() {
+        window.location = window.location + "#loaded";
+    }, 0);
+  }
 }
 
 // Sets the title.
 function setTitle(title) {
   var holder = document.getElementById('titleHolder');
 
   holder.textContent = title;
   document.title = title;
 }
 
@@ skipping 342 matching lines @@
       clampedScale = scaling;
       restoreCenter();
     }
   };
 }());
 
 window.addEventListener('touchstart', pincher.handleTouchStart, false);
 window.addEventListener('touchmove', pincher.handleTouchMove, false);
 window.addEventListener('touchend', pincher.handleTouchEnd, false);
 window.addEventListener('touchcancel', pincher.handleTouchCancel, false);