From 4797ddfb6b7ebd20eb32745d956fe4f7415b6718 Mon Sep 17 00:00:00 2001
From: YUKI Hiroshi <shimoda@clear-code.com>
Date: Fri, 21 Dec 2012 13:55:32 +0900
Subject: [PATCH] Don't raise error while dragging of non-tab objects over the
 tab bar

---
 modules/tabbarDNDObserver.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/tabbarDNDObserver.js b/modules/tabbarDNDObserver.js
index 0544c1bd..ae637b6b 100644
--- a/modules/tabbarDNDObserver.js
+++ b/modules/tabbarDNDObserver.js
@@ -267,7 +267,7 @@ catch(e) {
 			};
 
 		let draggedTab = aEvent.dataTransfer && aEvent.dataTransfer.mozGetDataAt(TAB_DROP_TYPE, 0);
-		if (draggedTab._dragData) {
+		if (draggedTab && draggedTab._dragData) {
 			let sameTypeUndraggedTabs = tabs.filter(function(aTab) { 
 					return !aTab._dragData && aTab.pinned == draggedTab.pinned;
 				});