PDF: Do more robust page number parsing in OOP plugin.

BUG=64309

Review URL: https://codereview.chromium.org/492433003

Cr-Commit-Position: refs/heads/master@{#290770}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@290770 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/resources/pdf/pdf.js

@@ -287,8 +287,10 @@ PDFViewer.prototype = {
     // Order is important as later actions can override the effects
     // of previous actions.
     if ('page' in paramsDictionary) {
-      // value is 1-based.
-      this.viewport_.goToPage(paramsDictionary['page'] - 1);
+      // |pageNumber| is 1-based, but goToPage() take a zero-based page number.
+      var pageNumber = parseInt(paramsDictionary['page']);
+      if (!isNaN(pageNumber))
+        this.viewport_.goToPage(pageNumber - 1);
     }
   },
 

chrome/browser/resources/pdf/viewport.js

@@ -450,7 +450,7 @@ Viewport.prototype = {
 
   /**
    * Go to the given page index.
-   * @param {number} page the index of the page to go to.
+   * @param {number} page the index of the page to go to. zero-based.
    */
   goToPage: function(page) {
     this.mightZoom_(function() {