Datepicker: Fixed #5085 bug in findPos for RTL languages

Author: kbwood

ui/jquery.ui.datepicker.js

@@ -730,8 +730,10 @@ $.extend(Datepicker.prototype, {
 
 	/* Find an object's position on the screen. */
 	_findPos: function(obj) {
+		var inst = this._getInst(obj);
+		var isRTL = this._get(inst, 'isRTL');
         while (obj && (obj.type == 'hidden' || obj.nodeType != 1)) {
-            obj = obj.nextSibling;
+            obj = obj[isRTL ? 'previousSibling' : 'nextSibling'];
         }
         var position = $(obj).offset();
 	    return [position.left, position.top];