REST API: Add 'delete_widget' action to delete widget endpoint

Triggers the 'delete_widget' action to the delete widget endpoint in the REST
API. This aligns with the behaviour in the widgets WP Admin screen.

Fixes #53289.
Props isabel_brison, TimothyBlynJacobs.


git-svn-id: https://develop.svn.wordpress.org/trunk@51060 602fd350-edb4-49c9-b593-d223f7449a82

Author: noisysocks

src/wp-includes/rest-api/endpoints/class-wp-rest-widgets-controller.php

@@ -321,6 +321,9 @@ public function delete_item( $request ) {
 			);
 			$_REQUEST = $_POST;
 
+			/** This action is documented in wp-admin/widgets-form.php */
+			do_action( 'delete_widget', $widget_id, $sidebar_id, $id_base );
+
 			$callback = $wp_registered_widget_updates[ $id_base ]['callback'];
 			$params   = $wp_registered_widget_updates[ $id_base ]['params'];