From 299ff0ecb36165a65339f315fbff9136e63bb20a Mon Sep 17 00:00:00 2001
From: Kris Maglione <maglione.k@gmail.com>
Date: Mon, 27 Dec 2010 01:51:33 -0500
Subject: [PATCH] Make it impossible for util.computedStyle to return null.
 Closes issue #180.

---
 common/modules/util.jsm | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/common/modules/util.jsm b/common/modules/util.jsm
index 4c769000..9885a1e8 100644
--- a/common/modules/util.jsm
+++ b/common/modules/util.jsm
@@ -353,13 +353,15 @@ var Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]),
         while (!(node instanceof Ci.nsIDOMElement) && node.parentNode)
             node = node.parentNode;
         try {
-            return node.ownerDocument.defaultView.getComputedStyle(node, null);
+            var res = node.ownerDocument.defaultView.getComputedStyle(node, null);
         }
-        catch (e) {
-            util.reportError(e);
-            util.dump(String(node));
+        catch (e) {}
+        if (res == null) {
+            util.dumpStack("Computed style is null: " + node);
+            Cu.reportError(Error("Computed style is null: " + node));
             return {};
         }
+        return res;
     },
 
     /**