Extension SW - add basic push messaging tests.

chrome/test/data/extensions/api_test/service_worker/push_messaging/sw.js

Index: chrome/test/data/extensions/api_test/service_worker/push_messaging/sw.js
diff --git a/chrome/test/data/extensions/api_test/service_worker/push_messaging/sw.js b/chrome/test/data/extensions/api_test/service_worker/push_messaging/sw.js
new file mode 100644
index 0000000000000000000000000000000000000000..2a5f5f95cb90148f810cc37fdffe372f3b3b41d5
--- /dev/null
+++ b/chrome/test/data/extensions/api_test/service_worker/push_messaging/sw.js
@@ -0,0 +1,30 @@
+// Copyright 2015 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.
+
+var portForNotifyingPushMessaging = null;
+var pushData = null;
+
+this.onpush = function(e) {

[Devlin, 2015/11/18 23:42:06]

nit: I think this can be a little cleaner:

var port;
var pushData;

function maybeFinish() {
  if (port && pushData)
    port.postMessage(pushData);
}

this.onpush = function(e) {
  pushData = e.data.text();
  maybeFinish();
};

this.onmessage = function(e) {
  ...
  port = e.ports[0];
  maybeFinish();
}

[lazyboy, 2015/11/19 02:40:28]

Thanks. Done.

+  var data = e.data.text();
+  if (waitingForPushMessaging) {
+    portForNotifyingPushMessaging.postMessage(data);
+  } else {
+    pushData = data;
+  }
+};
+
+this.onmessage = function(e) {
+  switch (e.data) {
+    case 'waitForPushMessaging':
+      portForNotifyingPushMessaging = e.ports[0];
+      if (pushData) {
+        e.ports[0].postMessage(pushData);
+      } else {
+        waitingForPushMessaging = true;
+      }
+      break;
+    default:
+      break;
+  }
+};