Navigation to relative fragments does not work correctly for OOP pdf.

chrome/browser/resources/pdf/open_pdf_params_parser.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.
 
 'use strict';
 
 /**
  * Creates a new OpenPDFParamsParser. This parses the open pdf parameters
  * passed in the url to set initial viewport settings for opening the pdf.
  * @param {string} url to be parsed.
  */
 function OpenPDFParamsParser(url) {
-  this.url_ = url;
   this.urlParams = {};
-  this.parseOpenPDFParams_();
+  // This will have name of all the nameddest from the loaded PDF.

[raymes, 2015/01/14 00:19:00]

nit: // A dictionary of all the named destinations in the PDF.

[Deepak, 2015/01/14 06:29:01]

Done.

+  this.namedDestinations = {};
 }
 
 OpenPDFParamsParser.prototype = {
   /**
    * @private
    * Parse zoom parameter of open PDF parameters. If this
    * parameter is passed while opening PDF then PDF should be opened
    * at the specified zoom level.
    * @param {number} zoom value.
    */
@@ skipping 15 matching lines @@
 
     // Handle #zoom=scale,left,top.
     var position = {x: parseFloat(paramValueSplit[1]),
                     y: parseFloat(paramValueSplit[2])};
     this.urlParams['position'] = position;
     this.urlParams['zoom'] = zoomFactor;
   },
 
   /**
    * @private
-   * Parse open PDF parameters. These parameters are mentioned in the url
+   * Parse PDF url parameters. These parameters are mentioned in the url
    * and specify actions to be performed when opening pdf files.
    * See http://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/
    * pdfs/pdf_open_parameters.pdf for details.
+   * @param {string} inputUrl that need to be parsed.
+   * @return {Object} urlParams data that have the PDF url parameter info.
    */
-  parseOpenPDFParams_: function() {
-    var originalUrl = this.url_;
+  getURLPDFParams: function(inputUrl) {
+    var originalUrl = inputUrl;
     var paramIndex = originalUrl.search('#');
     if (paramIndex == -1)
       return;
-
     var paramTokens = originalUrl.substring(paramIndex + 1).split('&');
     var paramsDictionary = {};
     for (var i = 0; i < paramTokens.length; ++i) {
       var keyValueSplit = paramTokens[i].split('=');
       if (keyValueSplit.length != 2)
         continue;
       paramsDictionary[keyValueSplit[0]] = keyValueSplit[1];
     }
+    if ('zoom' in paramsDictionary)
+      this.parseZoomParam_(paramsDictionary['zoom']);
+    return this.urlParams;
+  },
 
-    if ('page' in paramsDictionary) {
-      // |pageNumber| is 1-based, but goToPage() take a zero-based page number.
-      var pageNumber = parseInt(paramsDictionary['page']);
-      if (!isNaN(pageNumber))
-        this.urlParams['page'] = pageNumber - 1;
+  /**
+   * @private
+   * Helper function to give the page number after parsing url based on page,
+   * nameddest and nameddest with some value. These parameters are mentioned in
+   * the url and specify actions to be performed when opening pdf files.
+   * See http://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/
+   * pdfs/pdf_open_parameters.pdf for details.
+   * @param {string} inputUrl that need to be parsed to get pageNumber.
+   * @return {number} page number info for scrolling PDF file.
+   */
+  getInitalPage: function(inputUrl) {
+    var originalUrl = inputUrl;
+    var finalPageNumber = -1;
+    var paramIndex = originalUrl.search('#');
+    if (paramIndex == -1)
+      return finalPageNumber;
+
+    var paramTokens = originalUrl.substring(paramIndex + 1).split('&');
+    if ((paramTokens.length == 1) && (paramTokens[0].search('=') == -1)) {
+      return this.namedDestinations[paramTokens[0]];
     }
 
-    if ('zoom' in paramsDictionary)
-      this.parseZoomParam_(paramsDictionary['zoom']);
-  }
+    for (var i = 0; i < paramTokens.length; ++i) {
+      var keyValueSplit = paramTokens[i].split('=');
+      if (keyValueSplit.length != 2)
+        continue;
+      if (keyValueSplit[0] == 'page') {
+        var pageNumber = parseInt(keyValueSplit[1]);
+        if (!isNaN(pageNumber) && pageNumber > 0)
+          finalPageNumber = pageNumber - 1;
+        continue;
+      }
+      if (keyValueSplit[0] == 'nameddest') {
+        var pageNumber = this.namedDestinations[keyValueSplit[1]];
+        if (!isNaN(pageNumber) && pageNumber >= 0)
+          finalPageNumber = pageNumber;
+        continue;
+      }
+    }
+    return finalPageNumber;
+  },

[raymes, 2015/01/14 00:19:00]

I don't think we need to add a new function to parse the URL. We already parse
the URL in getURLPDFParams. We just need to add the part the looks up the
nameddest if it exists and alter the page number, as I mentioned earlier.

Maybe you're concerned that we're no longer really returning "url params"
anymore. That's ok we should just change the name of the function to
"getInitialViewport" (or something similar)

[Deepak, 2015/01/14 06:29:01]

I understood your meaning, I am removing getInitialPage() and we get required
info from getURLPDFParams(), that already have input url parsed info.
and in navigate_() in pdf.js we can get the page number for the tag like #US in
our case, as we already have this.paramsParser.namedDestinations{} ready here,so
we can completely avoid, parsing url to get the page number for navigate_.
only we need to prepare nameddest from urlFragment to pass it to 
this.paramsParser.namedDestinations[]. 

Thanks for suggestion and guidance.
I have made the changes.
Thanks

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