Theme Customizer: Integrate with browser history. Use window.history by default, with window.onhashchange as a fallback. fixes #20337, see #19910.

git-svn-id: https://develop.svn.wordpress.org/trunk@20488 602fd350-edb4-49c9-b593-d223f7449a82

wp-includes/theme.php

@@ -1590,6 +1590,7 @@ add_action( 'plugins_loaded', '_wp_customize_include' );
 function _wp_customize_loader_localize() {
 	wp_localize_script( 'customize-loader', 'wpCustomizeLoaderL10n', array(
 		'back' => sprintf( __( '← Return to %s' ), get_admin_page_title() ),
+		'url'  => admin_url( 'admin.php' ),
 	) );
 }
 add_action( 'admin_enqueue_scripts', '_wp_customize_loader_localize' );