From 0a4115365e2c2f5e23bb3f9bba5a127651482026 Mon Sep 17 00:00:00 2001
From: Kyle Huey <khuey@kylehuey.com>
Date: Mon, 1 Feb 2016 09:44:52 -0800
Subject: [PATCH] Bug 1244582: Add back in a null check that was accidentally
 removed. r=smaug

---
 dom/events/EventStateManager.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/dom/events/EventStateManager.cpp b/dom/events/EventStateManager.cpp
index 2df384e7cc0..a324f80eb75 100644
--- a/dom/events/EventStateManager.cpp
+++ b/dom/events/EventStateManager.cpp
@@ -2006,6 +2006,7 @@ EventStateManager::GetContentViewer(nsIContentViewer** aCv)
 
   nsCOMPtr<mozIDOMWindowProxy> focusedWindow;
   fm->GetFocusedWindow(getter_AddRefs(focusedWindow));
+  if (!focusedWindow) return NS_ERROR_FAILURE;
 
   auto* ourWindow = nsPIDOMWindowOuter::From(focusedWindow);