Docs: Add much more complete and syntactically correct documentation throughout the `WP_REST_User_Meta_Fields` class.

Props Soean, mrahmadawais, flixos90.
See #38398.


git-svn-id: https://develop.svn.wordpress.org/trunk@39034 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/rest-api/fields/class-wp-rest-user-meta-fields.php

@@ -1,19 +1,40 @@
 <?php
+/**
+ * REST API: WP_REST_User_Meta_Fields class
+ *
+ * @package WordPress
+ * @subpackage REST_API
+ * @since 4.7.0
+ */
 
+/**
+ * Core class used to manage meta values for users via the REST API.
+ *
+ * @since 4.7.0
+ *
+ * @see WP_REST_Meta_Fields
+ */
 class WP_REST_User_Meta_Fields extends WP_REST_Meta_Fields {
+
 	/**
-	 * Get the object type for meta.
+	 * Retrieves the object meta type.
 	 *
-	 * @return string
+	 * @since 4.7.0
+	 * @access protected
+	 *
+	 * @return string The user meta type.
 	 */
 	protected function get_meta_type() {
 		return 'user';
 	}
 
 	/**
-	 * Get the type for `register_rest_field`.
+	 * Retrieves the type for register_rest_field().
 	 *
-	 * @return string
+	 * @since 4.7.0
+	 * @access public
+	 *
+	 * @return string The user REST field type.
 	 */
 	public function get_rest_field_type() {
 		return 'user';