From 86b8cafec6da67f977bb7a73766f584e9420bc4d Mon Sep 17 00:00:00 2001
From: Justin Lebar <justin.lebar@gmail.com>
Date: Mon, 29 Apr 2013 18:12:11 -0400
Subject: [PATCH] Bug 852847 - Part 5: Fix assertions caused by part 4. r=me

---
 dom/browser-element/BrowserElementChildPreload.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/dom/browser-element/BrowserElementChildPreload.js b/dom/browser-element/BrowserElementChildPreload.js
index cccd80ab3715..443bcc8b1b35 100644
--- a/dom/browser-element/BrowserElementChildPreload.js
+++ b/dom/browser-element/BrowserElementChildPreload.js
@@ -326,7 +326,9 @@ BrowserElementChild.prototype = {
     let returnValue = win.modalReturnValue;
     delete win.modalReturnValue;
 
-    utils.leaveModalStateWithWindow(modalStateWin);
+    if (!this._shuttingDown) {
+      utils.leaveModalStateWithWindow(modalStateWin);
+    }
 
     debug("Leaving modal state (outerID=" + outerWindowID + ", " +
                                "innerID=" + innerWindowID + ")");