Dispatch push event to worker from PushServiceImpl#OnMessage.

content/public/common/push_messaging_status.h

Index: content/public/common/push_messaging_status.h
diff --git a/content/public/common/push_messaging_status.h b/content/public/common/push_messaging_status.h
index 1b77c1452f9aef16a344ce8de7afbea33b621132..9e9694f87e3d7379a0b22875c64550a68ee946be 100644
--- a/content/public/common/push_messaging_status.h
+++ b/content/public/common/push_messaging_status.h
@@ -27,6 +27,12 @@ enum PushMessagingStatus {
   // Registration failed in the push service implemented by the embedder.
   PUSH_MESSAGING_STATUS_REGISTRATION_FAILED_SERVICE_ERROR,
 
+  // The message could not be delivered because no service worker was found.
+  PUSH_MESSAGING_STATUS_MESSAGE_DELIVERY_FAILED_NO_SERVICE_WORKER,
+
+  // The message could not be delivered because of a service worker error.
+  PUSH_MESSAGING_STATUS_MESSAGE_DELIVERY_FAILED_SERVICE_WORKER_ERROR,
+
   // Generic error (a more specific error should be used whenever possible).
   PUSH_MESSAGING_STATUS_ERROR,