Script Loader: Add the $group parameter to WP_Dependencies::do_item().

Previously, the method was called with two parameters in `::do_items()`, while the method signature only included one parameter.

Technically, this was not an issue as `WP_Dependencies::do_item()` is a placeholder meant to be overwritten when extending the class. When handling scripts, `WP_Dependencies` is extended with `WP_Scripts`, and the `$group` parameter was only used in `WP_Scripts::do_item()`, which does expect a second argument.

However, officially adding the parameter to `WP_Dependencies::do_item()` signature prevents code misunderstanding and avoids a warning in PHP code inspection tools.

Props kaggdesign, soulseekah, azaozz, SergeyBiryukov.
Fixes #43627.
Built from https://develop.svn.wordpress.org/trunk@47769


git-svn-id: http://core.svn.wordpress.org/trunk@47545 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class.wp-styles.php

@@ -139,13 +139,16 @@ class WP_Styles extends WP_Dependencies {
 	 * Processes a style dependency.
 	 *
 	 * @since 2.6.0
+	 * @since 5.5.0 Added the `$group` parameter.
 	 *
 	 * @see WP_Dependencies::do_item()
 	 *
-	 * @param string $handle The style's registered handle.
+	 * @param string    $handle The style's registered handle.
+	 * @param int|false $group  Optional. Group level: level (int), no groups (false).
+	 *                          Default false.
 	 * @return bool True on success, false on failure.
 	 */
-	public function do_item( $handle ) {
+	public function do_item( $handle, $group = false ) {
 		if ( ! parent::do_item( $handle ) ) {
 			return false;
 		}