Prevent accidental body class concatenation by replacing (no-)customize-support with a space

The regular expression used by wp_customize_support_script() replaces all spaces
surrounding the matching class. This caused other classes to be merged together.

Props johnpbloch, SergeyBiryukov. Fixes #22103.


git-svn-id: http://core.svn.wordpress.org/trunk@22132 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/theme.php

@@ -1686,7 +1686,7 @@ function wp_customize_support_script() {
 			request = true;
 <?php		endif; ?>
 
-			b[c] = b[c].replace( rcs, '' );
+			b[c] = b[c].replace( rcs, ' ' );
 			b[c] += ( window.postMessage && request ? ' ' : ' no-' ) + cs;
 		}());
 	</script>