Fix safebrowsing code that assumed x: 1, get x() was permitted. r=orange

--HG--
extra : rebase_source : ee9e81305de0daa2039b2f84104b95911cc6dfe6

browser/components/safebrowsing/content/sb-loader.js

@@ -35,8 +35,6 @@
 # ***** END LICENSE BLOCK *****
 
 var safebrowsing = {
-  appContext: null,
-
   startup: function() {
     setTimeout(function() {
       safebrowsing.deferredStartup();