[WIP] Support PerformanceResourceTiming for Service Worker Navigation Preload

third_party/WebKit/LayoutTests/http/tests/serviceworker/navigation-preload/chromium/resources/navigation-preload-resource-timing-worker.js

Index: third_party/WebKit/LayoutTests/http/tests/serviceworker/navigation-preload/chromium/resources/navigation-preload-resource-timing-worker.js
diff --git a/third_party/WebKit/LayoutTests/http/tests/serviceworker/navigation-preload/chromium/resources/navigation-preload-resource-timing-worker.js b/third_party/WebKit/LayoutTests/http/tests/serviceworker/navigation-preload/chromium/resources/navigation-preload-resource-timing-worker.js
new file mode 100644
index 0000000000000000000000000000000000000000..cc0a44f9e64e4bd5edf334c0cf7a61cee916afd7
--- /dev/null
+++ b/third_party/WebKit/LayoutTests/http/tests/serviceworker/navigation-preload/chromium/resources/navigation-preload-resource-timing-worker.js
@@ -0,0 +1,13 @@
+self.addEventListener('activate', event => {
+    event.waitUntil(self.registration.navigationPreload.enable());
+  });
+
+self.addEventListener('fetch', event => {
+    event.respondWith(
+      event.preloadResponse
+          .then(response => response.text())
+          .then(text =>
+            new Response(
+              JSON.stringify({timingEntries: performance.getEntries()}),
+              {headers: {'Content-Type': 'text/html'}})));
+  });