Fix setPreferences regression from the e10s patch (PR 5115)

extensions/firefox/content/PdfjsChromeUtils.jsm

@@ -1,3 +1,5 @@
+/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
 /* Copyright 2012 Mozilla Foundation
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -23,7 +25,7 @@ const Ci = Components.interfaces;
 const Cr = Components.results;
 const Cu = Components.utils;
 
-const PREF_PREFIX = 'pdfjs';
+const PREF_PREFIX = 'PDFJSSCRIPT_PREF_PREFIX';
 const PDF_CONTENT_TYPE = 'application/pdf';
 
 Cu.import('resource://gre/modules/XPCOMUtils.jsm');
@@ -176,7 +178,9 @@ let PdfjsChromeUtils = {
   },
 
   _isPrefAllowed: function (aPrefName) {
-    if (this._allowedPrefNames.indexOf(aPrefName) == -1) {
+    let unPrefixedName = aPrefName.split(PREF_PREFIX + '.');
+    if (unPrefixedName[0] !== '' ||
+        this._allowedPrefNames.indexOf(unPrefixedName[1]) === -1) {
       let msg = "'" + aPrefName + "' ";
       msg += "can't be accessed from content. See PdfjsChromeUtils." 
       throw new Error(msg);

make.js

@@ -680,6 +680,8 @@ target.firefox = function() {
       FIREFOX_BUILD_CONTENT_DIR + 'PdfStreamConverter.jsm');
   sed('-i', /PDFJSSCRIPT_MOZ_CENTRAL/, 'false',
       FIREFOX_BUILD_CONTENT_DIR + 'PdfStreamConverter.jsm');
+  sed('-i', /PDFJSSCRIPT_PREF_PREFIX/, FIREFOX_PREF_PREFIX,
+      FIREFOX_BUILD_CONTENT_DIR + 'PdfjsChromeUtils.jsm');
 
   // Update localized metadata
   var localizedMetadata = cat(EXTENSION_SRC_DIR + '/firefox/metadata.inc');
@@ -808,6 +810,8 @@ target.mozcentral = function() {
       MOZCENTRAL_CONTENT_DIR + 'PdfStreamConverter.jsm');
   sed('-i', /PDFJSSCRIPT_MOZ_CENTRAL/, 'true',
       MOZCENTRAL_CONTENT_DIR + 'PdfStreamConverter.jsm');
+  sed('-i', /PDFJSSCRIPT_PREF_PREFIX/, MOZCENTRAL_PREF_PREFIX,
+      MOZCENTRAL_CONTENT_DIR + 'PdfjsChromeUtils.jsm');
 
   // Copy test files
   mkdir('-p', MOZCENTRAL_TEST_DIR);