Source

File: wp-admin/includes/class-wp-site-health.php

public function __construct() {
		$this->maybe_create_scheduled_event();

		// Save memory limit before it's affected by wp_raise_memory_limit( 'admin' ).
		$this->php_memory_limit = ini_get( 'memory_limit' );

		$this->timeout_late_cron   = 0;
		$this->timeout_missed_cron = - 5 * MINUTE_IN_SECONDS;

		if ( defined( 'DISABLE_WP_CRON' ) && DISABLE_WP_CRON ) {
			$this->timeout_late_cron   = - 15 * MINUTE_IN_SECONDS;
			$this->timeout_missed_cron = - 1 * HOUR_IN_SECONDS;
		}

		add_filter( 'admin_body_class', array( $this, 'admin_body_class' ) );

		add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_scripts' ) );
		add_action( 'wp_site_health_scheduled_check', array( $this, 'wp_cron_scheduled_check' ) );
	}