Datepicker: Removed duplicate call to _updateDatepicker when changing…

… option in Firefox. Fixed #7322 - datepicker: Year would disappear when changing option.

(cherry picked from commit a645630)

ui/jquery.ui.datepicker.js

@@ -455,7 +455,8 @@ $.extend(Datepicker.prototype, {
 				inst.settings.maxDate = this._formatDate(inst, maxDate);
 			this._attachments($(target), inst);
 			this._autoSize(inst);
-			this._setDateDatepicker(target, date);
+			this._setDate(inst, date);
+			this._updateAlternate(inst);
 			this._updateDatepicker(inst);
 		}
 	},