Bug 349128 - Focus lost pressing enter in empty location bar. r=gavin.

git-svn-id: svn://10.0.0.236/trunk@215282 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/browser/base/content/browser.js

@@ -2271,6 +2271,9 @@ function handleURLBarRevert()
 }
 
 function handleURLBarCommand(aTriggeringEvent) {
+  if (!gURLBar.value)
+    return;
+
   var postData = { };
   canonizeUrl(aTriggeringEvent, postData);