Rename wp.xhr to wp.ajax to match admin-ajax.php (which it uses), jQuery.ajax (which it wraps), etc. see #24424.

git-svn-id: https://develop.svn.wordpress.org/trunk@24652 602fd350-edb4-49c9-b593-d223f7449a82

wp-includes/script-loader.php

@@ -269,7 +269,7 @@ function wp_default_scripts( &$scripts ) {
 
 	$scripts->add( 'wp-util', "/wp-includes/js/wp-util$suffix.js", array('underscore', 'jquery'), false, 1 );
 	did_action( 'init' ) && $scripts->localize( 'wp-util', '_wpUtilSettings', array(
-		'xhr' => array(
+		'ajax' => array(
 			'url' => admin_url( 'admin-ajax.php', 'relative' ),
 		),
 	) );