From e69a8417dac86d2ece9ac8520fc26d016932857b Mon Sep 17 00:00:00 2001
From: "sspitzer%netscape.com" <sspitzer%netscape.com>
Date: Wed, 17 Nov 1999 23:05:29 +0000
Subject: [PATCH] fix for #19117, crash.  add check before dereferencing null.

---
 dom/src/base/nsGlobalWindow.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/dom/src/base/nsGlobalWindow.cpp b/dom/src/base/nsGlobalWindow.cpp
index ea22ae2302c9..fc21742acb15 100644
--- a/dom/src/base/nsGlobalWindow.cpp
+++ b/dom/src/base/nsGlobalWindow.cpp
@@ -2620,9 +2620,11 @@ GlobalWindowImpl::GetBrowserWindowInterface(
   NS_ENSURE_TRUE(aWebShell, NS_ERROR_UNEXPECTED);
 
   nsCOMPtr<nsIWebShellContainer> topLevelWindow;
+
+  // fix me! not returning NS_ERROR_FAILURE if topLevelWindow is null.
   NS_ENSURE_SUCCESS(aWebShell->GetTopLevelWindow(
       getter_AddRefs(topLevelWindow)), NS_ERROR_FAILURE);
-  
+  if (!topLevelWindow) return NS_ERROR_FAILURE;
   return topLevelWindow->QueryInterface(NS_GET_IID(nsIBrowserWindow), (void**)&aBrowser);
 }