Pass load events from prerenders to launching elements.

chrome/test/data/prerender/prerender_events_common.js

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Common js for prerender loaders; defines the helper functions that put
+// event handlers on prerenders and track the events for browser tests.
+
+// TODO(gavinp): Put more common loader logic in here.
+
+// Currently only errors with the ordering of Prerender events are caught.
+var hadPrerenderEventErrors = false;
+
+var receivedPrerenderStartEvents = [];
+var receivedPrerenderLoadEvents = [];
+var receivedPrerenderStopEvents = [];
+
+function PrerenderStartHandler(index) {
+  if (receivedPrerenderStartEvents[index] ||
+      receivedPrerenderLoadEvents[index] ||
+      receivedPrerenderStopEvents[index]) {
+    hadPrerenderEventErrors = true;
+    return;
+  }
+  receivedPrerenderStartEvents[index] = true;
+}
+
+function PrerenderLoadHandler(index) {
+  if (!receivedPrerenderStartEvents[index] ||
+      receivedPrerenderLoadEvents[index] ||
+      receivedPrerenderStopEvents[index]) {
+    hadPrerenderEventErrors = true;
+    return;
+  }
+  receivedPrerenderLoadEvents[index] = true;
+}
+
+function PrerenderStopHandler(index) {
+  if (!receivedPrerenderStartEvents[index] ||
+      receivedPrerenderStopEvents[index]) {
+    hadPrerenderEventErrors = true;
+    return;
+  }
+  receivedPrerenderStopEvents[index] = true;
+}
+
+function AddEventHandlersToLinkElement(link, index) {
+  link.addEventListener('webkitprerenderstart',
+                        PrerenderStartHandler.bind(null, index), false);
+  link.addEventListener('webkitprerenderload',
+                        PrerenderLoadHandler.bind(null, index), false);
+  link.addEventListener('webkitprerenderstop',
+                        PrerenderStopHandler.bind(null, index), false);
+}