ss4upgrade: Added js fix to check for $this

Author: adunn

javascript/ImageSelect.jquery.js

@@ -185,7 +185,11 @@
                     }
                 });
             });
-            this.trigger('chosen:hiding_dropdown');
+
+            if (typeof $this !== 'undefined') {
+                $this.trigger('chosen:hiding_dropdown');
+            }
+
             return ret;
         }
     });