From f6296b1cc9591a6ff6af2b2a25d4b99bdaeed790 Mon Sep 17 00:00:00 2001
From: "dbaron%dbaron.org"
 <dbaron%dbaron.org@18797224-902f-48f8-a5cc-f745e15eee43>
Date: Sat, 6 Nov 2004 07:59:46 +0000
Subject: [PATCH] Null-check for unreproducable topcrash.  b=267804  r+sr=jst

git-svn-id: svn://10.0.0.236/trunk@165057 18797224-902f-48f8-a5cc-f745e15eee43
---
 mozilla/docshell/base/nsDocShell.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/mozilla/docshell/base/nsDocShell.cpp b/mozilla/docshell/base/nsDocShell.cpp
index b18b7a86384..fab4fbae155 100644
--- a/mozilla/docshell/base/nsDocShell.cpp
+++ b/mozilla/docshell/base/nsDocShell.cpp
@@ -3342,6 +3342,13 @@ nsDocShell::GetVisibility(PRBool * aVisibility)
         nsCOMPtr<nsIPresShell> pPresShell;
         parentDS->GetPresShell(getter_AddRefs(pPresShell));
 
+        // Null-check for crash in bug 267804
+        if (!pPresShell) {
+            NS_NOTREACHED("docshell has null pres shell");
+            *aVisibility = PR_FALSE;
+            return NS_OK;
+        }
+
         nsIContent *shellContent =
             pPresShell->GetDocument()->FindContentForSubDocument(presShell->GetDocument());
         NS_ASSERTION(shellContent, "subshell not in the map");