Bug 211760. Crashing with Immersion Touchware. r=jgaunt, sr=jst

git-svn-id: svn://10.0.0.236/trunk@144819 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/accessible/src/base/nsDocAccessible.cpp

@@ -295,6 +295,9 @@ NS_IMETHODIMP nsDocAccessible::GetDocument(nsIDOMDocument **aDOMDoc)
 
 void nsDocAccessible::CheckForEditor()
 {
+  if (!mDocument) {
+    return;  // No document -- we've been shut down
+  }
   nsCOMPtr<nsIScriptGlobalObject> ourGlobal;
   mDocument->GetScriptGlobalObject(getter_AddRefs(ourGlobal));
   nsCOMPtr<nsIDOMWindow> domWindow(do_QueryInterface(ourGlobal));