Index: src/wp-admin/includes/admin-filters.php
===================================================================
--- src/wp-admin/includes/admin-filters.php	(revision 38034)
+++ src/wp-admin/includes/admin-filters.php	(working copy)
@@ -44,7 +44,9 @@
 add_action( 'admin_head', '_ipad_meta'               );
 
 // Prerendering.
-add_filter( 'admin_head', 'wp_resource_hints' );
+if ( ! is_customize_preview() ) {
+	add_filter( 'admin_print_styles', 'wp_resource_hints', 1 );
+}
 
 add_action( 'admin_print_scripts-post.php',     'wp_page_reload_on_back_button_js' );
 add_action( 'admin_print_scripts-post-new.php', 'wp_page_reload_on_back_button_js' );
Index: src/wp-includes/default-filters.php
===================================================================
--- src/wp-includes/default-filters.php	(revision 38034)
+++ src/wp-includes/default-filters.php	(working copy)
@@ -229,6 +229,7 @@
 // Actions
 add_action( 'wp_head',             '_wp_render_title_tag',            1     );
 add_action( 'wp_head',             'wp_enqueue_scripts',              1     );
+add_action( 'wp_head',             'wp_resource_hints',               2     );
 add_action( 'wp_head',             'feed_links',                      2     );
 add_action( 'wp_head',             'feed_links_extra',                3     );
 add_action( 'wp_head',             'rsd_link'                               );
@@ -242,7 +243,6 @@
 add_action( 'wp_head',             'wp_print_head_scripts',            9    );
 add_action( 'wp_head',             'wp_generator'                           );
 add_action( 'wp_head',             'rel_canonical'                          );
-add_action( 'wp_head',             'wp_resource_hints'                      );
 add_action( 'wp_head',             'wp_shortlink_wp_head',            10, 0 );
 add_action( 'wp_head',             'wp_site_icon',                    99    );
 add_action( 'wp_footer',           'wp_print_footer_scripts',         20    );
@@ -256,6 +256,7 @@
     add_action( 'wp_head', 'wp_no_robots' );
 
 // Login actions
+add_filter( 'login_head',          'wp_resource_hints',             8     );
 add_action( 'login_head',          'wp_print_head_scripts',         9     );
 add_action( 'login_head',          'print_admin_styles',            9     );
 add_action( 'login_head',          'wp_site_icon',                  99    );
@@ -416,6 +417,7 @@
 add_action( 'admin_enqueue_scripts', 'wp_localize_jquery_ui_datepicker', 1000 );
 add_filter( 'wp_print_scripts', 'wp_just_in_time_script_localization' );
 add_filter( 'print_scripts_array', 'wp_prototype_before_jquery' );
+add_filter( 'customize_controls_print_styles', 'wp_resource_hints', 1 );
 
 add_action( 'wp_default_styles', 'wp_default_styles' );
 add_filter( 'style_loader_src', 'wp_style_loader_src', 10, 2 );