Issue #3262183 by daffie, longwave: Remove DrupalKernelLegacyTest

<?php

namespace Drupal\Tests\Core\DrupalKernel;

use Drupal\Core\DrupalKernel;

use Drupal\Tests\UnitTestCase;

use Symfony\Component\HttpFoundation\Request;

use Symfony\Component\HttpKernel\Event\KernelEvent;

/**

 * @coversDefaultClass \Drupal\Core\DrupalKernel

 * @group legacy

 */

class DrupalKernelLegacyTest extends UnitTestCase {

  /**

   * Tests deprecation message in overridden KernelEvent.

   *

   * @covers ::isMasterRequest

   */

  public function testKernelEventDeprecation() {

    $kernel = $this->createMock(DrupalKernel::class);

    $request = $this->createMock(Request::class);

    $event = new KernelEvent($kernel, $request, $kernel::MAIN_REQUEST);

    $this->expectDeprecation('Since symfony/http-kernel 5.3: "Symfony\Component\HttpKernel\Event\KernelEvent::isMasterRequest()" is deprecated, use "isMainRequest()" instead.');

    $this->assertTrue($event->isMasterRequest());

  }

}