Fix for PDFs with lots of named destinations take a long time to load.

chrome/browser/resources/pdf/navigator.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.
 
 'use strict';
 
 /**
  * Creates a new Navigator for navigating to links inside or outside the PDF.
  * @param {string} originalUrl The original page URL.
  * @param {Object} viewport The viewport info of the page.
@@ skipping 56 matching lines @@
         url == 'https://' ||
         url == 'ftp://' ||
         url == 'file://' ||
         url == 'mailto:') {
       return;
     }
 
     if (newTab) {
       this.navigateInNewTabCallback_(url);
     } else {
-      var pageNumber =
-          this.paramsParser_.getViewportFromUrlParams(url).page;
-      if (pageNumber != undefined)
-        this.viewport_.goToPage(pageNumber);
-      else
-        this.navigateInCurrentTabCallback_(url);
+      this.paramsParser_.getViewportFromUrlParams(
+          url, function(initialViewport) {

[raymes, 2015/02/16 02:02:30]

nit: initialViewport->viewportPosition 
nit: could you pull this function out into a separate function in the class
called onViewportReceived?

[Deepak, 2015/02/16 06:45:37]

Done.

+            var pageNumber = initialViewport.page;
+            if (pageNumber != undefined)
+              this.viewport_.goToPage(pageNumber);
+            else
+              this.navigateInCurrentTabCallback_(url);
+          }.bind(this));
     }
   }
 };