From 1b9c964e8138dbe7d8b3a8463a6cdbebf14a0acc Mon Sep 17 00:00:00 2001
From: Weston Ruter <westonruter@git.wordpress.org>
Date: Mon, 10 Apr 2017 21:14:50 +0000
Subject: [PATCH] Customize: Verify availability of `history.replaceState` (in
 IE9) before attempting to populate `changeset_uuid` parameter.

Props westonruter, timmydcrawford for testing.
Amends [39686].
See #39227.
Fixes #40405.


git-svn-id: https://develop.svn.wordpress.org/trunk@40405 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-admin/js/customize-controls.js | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/wp-admin/js/customize-controls.js b/src/wp-admin/js/customize-controls.js
index e038dcc8fa..d340a1ba04 100644
--- a/src/wp-admin/js/customize-controls.js
+++ b/src/wp-admin/js/customize-controls.js
@@ -4762,6 +4762,12 @@
 			 */
 			populateChangesetUuidParam = function( isIncluded ) {
 				var urlParser, queryParams;
+
+				// Abort on IE9 which doesn't support history management.
+				if ( ! history.replaceState ) {
+					return;
+				}
+
 				urlParser = document.createElement( 'a' );
 				urlParser.href = location.href;
 				queryParams = api.utils.parseQueryString( urlParser.search.substr( 1 ) );
@@ -4780,11 +4786,9 @@
 				history.replaceState( {}, document.title, urlParser.href );
 			};
 
-			if ( history.replaceState ) {
-				changesetStatus.bind( function( newStatus ) {
-					populateChangesetUuidParam( '' !== newStatus && 'publish' !== newStatus );
-				} );
-			}
+			changesetStatus.bind( function( newStatus ) {
+				populateChangesetUuidParam( '' !== newStatus && 'publish' !== newStatus );
+			} );
 
 			// Expose states to the API.
 			api.state = state;