chromium/src/third_party/blink/web_tests/http/tests/inspector-protocol/network/raw-headers-after-navigation.js

(async function(testRunner) {
  var {page, session, dp} = await testRunner.startBlank(
    `Tests that raw response headers are correctly reported after navigation.\n`
  );

  async function fetchAndLogResponseStatus() {
    session.evaluate(`fetch('http://devtools.test:8000/devtools/network/resources/resource.php?cached=1')`);
    const response = (await dp.Network.onceResponseReceived()).params.response;
    testRunner.log('Response status: ' + response.status);
  }

  await dp.Page.enable();
  await dp.Network.enable();
  await dp.Page.navigate({url: 'http://devtools.test:8000/inspector-protocol/network/resources/hello-world.html'});

  testRunner.log('Fetching resource:');
  await fetchAndLogResponseStatus();

  testRunner.log('Fetching same resource again:');
  await fetchAndLogResponseStatus();

  testRunner.completeTest();
})