Only trigger navigation in distiller if in print preview

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;
@@ skipping 25 matching lines @@
     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) {
+  if (isLastPage && typeof isPrintPreviewDistiller !== 'undefined'
+      && isPrintPreviewDistiller) {
     setTimeout(function() {
         window.location = window.location + "#loaded";
     }, 0);
   }
 }
 
 // Sets the title.
 function setTitle(title) {
   var holder = document.getElementById('titleHolder');
 
@@ skipping 346 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);