Theme Customizer: Load the preview iframe with the same scheme as the admin to prevent security warnings. props ocean90. fixes #20137, see #19910.

git-svn-id: http://svn.automattic.com/wordpress/trunk@20051 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/customize-controls.php

@@ -80,8 +80,10 @@ do_action( 'customize_controls_print_scripts' );
 
 	do_action( 'customize_controls_print_footer_scripts' );
 
+	// Check current scheme and load the preview with the same scheme
+	$scheme = is_ssl() ? 'https' : 'http';
 	$settings = array(
-		'preview' => esc_url( home_url( '/' ) ),
+		'preview' => esc_url( get_home_url( null, '/', $scheme ) ),
 		'values'  => array(),
 		'prefix'  => WP_Customize_Setting::name_prefix,
 	);