From af80e92ee1828c444948f6d0a31531b1b9dd49d6 Mon Sep 17 00:00:00 2001
From: Andrew Ozz <azaozz@git.wordpress.org>
Date: Mon, 10 Oct 2016 22:41:26 +0000
Subject: [PATCH] Editor: do not send the request for releasing the post lock
 on unload when post_ID or active_post_lock is missing.

Props dlh, adamsilverstein.
Fixes #38271.

git-svn-id: https://develop.svn.wordpress.org/trunk@38772 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-admin/js/post.js | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/src/wp-admin/js/post.js b/src/wp-admin/js/post.js
index af9015b977..b5424599d9 100644
--- a/src/wp-admin/js/post.js
+++ b/src/wp-admin/js/post.js
@@ -105,7 +105,7 @@ window.wp = window.wp || {};
 	 * Overwrite the content of the Featured Image postbox
 	 *
 	 * @param {string} html New HTML to be displayed in the content area of the postbox.
-	 * 
+	 *
 	 * @global
 	 */
 	WPSetThumbnailHTML = function(html){
@@ -499,21 +499,28 @@ jQuery(document).ready( function($) {
 			return;
 		}
 
+		var postID = $('#post_ID').val();
+		var postLock = $('#active_post_lock').val();
+
+		if ( ! postID || ! postLock ) {
+			return;
+		}
+
 		var data = {
 			action: 'wp-remove-post-lock',
 			_wpnonce: $('#_wpnonce').val(),
-			post_ID: $('#post_ID').val(),
-			active_post_lock: $('#active_post_lock').val()
+			post_ID: postID,
+			active_post_lock: postLock
 		};
 
-		if (window.FormData && window.navigator.sendBeacon) {
+		if ( window.FormData && window.navigator.sendBeacon ) {
 			var formData = new window.FormData();
 
-			$.each(data, function(key, value) {
-				formData.append(key, value);
+			$.each( data, function( key, value ) {
+				formData.append( key, value );
 			});
 
-			if (window.navigator.sendBeacon(ajaxurl, formData)) {
+			if ( window.navigator.sendBeacon( ajaxurl, formData ) ) {
 				return;
 			}
 		}