From d5b7a4ed878069e31e6087ed62fcdcf7b5673783 Mon Sep 17 00:00:00 2001
From: Ehsan Akhgari <ehsan@mozilla.com>
Date: Tue, 26 Feb 2013 11:31:35 -0500
Subject: [PATCH] Bug 845341 - Make sure that
 PrivateBrowsingUtils.permanentPrivateBrowsing does not throw if the autostart
 pref doesn't have a default value; r=jdm

---
 toolkit/content/PrivateBrowsingUtils.jsm | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/toolkit/content/PrivateBrowsingUtils.jsm b/toolkit/content/PrivateBrowsingUtils.jsm
index 52528d6c98e..f54396adfb5 100644
--- a/toolkit/content/PrivateBrowsingUtils.jsm
+++ b/toolkit/content/PrivateBrowsingUtils.jsm
@@ -27,8 +27,13 @@ this.PrivateBrowsingUtils = {
   },
 
   get permanentPrivateBrowsing() {
-    return gTemporaryAutoStartMode ||
-           Services.prefs.getBoolPref(kAutoStartPref, false);
+    try {
+      return gTemporaryAutoStartMode ||
+             Services.prefs.getBoolPref(kAutoStartPref);
+    } catch (e) {
+      // The pref does not exist
+      return false;
+    }
   },
 
   // These should only be used from internal code