Add Filter to make it possible to only add gutenberg links on a per p…

…ost type basis (#2528)

Right now, Gutenberg is not the right experience for all post types. In order to help encourage testing, we should make it possible to remove the quick action from certain post types.

See: https://meta.trac.wordpress.org/ticket/3065#comment:5

lib/register.php

@@ -90,8 +90,9 @@ function gutenberg_add_edit_links_filters() {
 function gutenberg_add_edit_links( $actions, $post ) {
 	$can_edit_post = current_user_can( 'edit_post', $post->ID );
 	$title = _draft_or_post_title( $post->ID );
+	$post_type = get_post_type( $post );
 
-	if ( $can_edit_post && 'trash' !== $post->post_status ) {
+	if ( $can_edit_post && 'trash' !== $post->post_status && apply_filters( 'gutenberg_add_edit_link_for_post_type', true, $post_type, $post ) ) {
 		// Build the Gutenberg edit action. See also: WP_Posts_List_Table::handle_row_actions().
 		$gutenberg_url = menu_page_url( 'gutenberg', false );
 		$gutenberg_action = sprintf(