Add new line at end of the file.

jquery.postMessage/jquery.postMessage.d.ts

@@ -41,4 +41,4 @@ interface JQueryStatic {
      * @param delay An optional zero-or-greater delay in milliseconds at which the polling loop will execute (for browser that don’t support window.postMessage). If omitted, defaults to 100.
      */
     receiveMessage(callback: (event: MessageEvent) => any, sourceOrigin?: (origin: string) => boolean, delay?: number): void;
-}
+}