Add a missing file header to wp-includes/class-wp-customize-manager.php, separate out the class DocBlock for `WP_Customize_Manager`.

See #31446.


git-svn-id: https://develop.svn.wordpress.org/trunk@31540 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-customize-manager.php

@@ -1,6 +1,14 @@
 <?php
 /**
- * Customize Manager.
+ * WordPress Customize Manager classes
+ *
+ * @package WordPress
+ * @subpackage Customize
+ * @since 3.4.0
+ */
+
+/**
+ * Customize Manager class.
  *
  * Bootstraps the Customize experience on the server-side.
  *
@@ -10,8 +18,6 @@
  * Serves as a factory for Customize Controls and Settings, and
  * instantiates default Customize Controls and Settings.
  *
- * @package WordPress
- * @subpackage Customize
  * @since 3.4.0
  */
 final class WP_Customize_Manager {