PlzNavigate: Make ServiceWorker work with PlzNavigate.

content/browser/service_worker/service_worker_navigation_handle.h

+// 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.
+
+#ifndef CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_NAVIGATION_HANDLE_H_
+#define CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_NAVIGATION_HANDLE_H_
+
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+
+namespace content {
+
+class ServiceWorkerContextWrapper;
+class ServiceWorkerNavigationHandleCore;
+
+// This class is used to manage the lifetime of ServiceWorkerProviderHosts
+// created during navigation. This is a UI thread class, with a pendant class
+// on the IO thread, the ServiceWorkerNavigationHandleCore.

[michaeln, 2015/10/20 22:12:53]

thnx for the nice doc comments!

+//
+// The lifetime of the ServiceWorkerNavigationHandle, the
+// ServiceWorkerNavigationHandleCore and the ServiceWorkerProviderHost are the
+// following :
+//   1) We create a ServiceWorkerNavigationHandle on the UI thread with a
+//   service worker provider id of -1. This also leads to the creation of a
+//   ServiceWorkerNavigationHandleCore with an id of -1.
+//
+//   2) When the navigation request is sent to the IO thread, we include a
+//   pointer to the ServiceWorkerNavigationHandleCore.
+//
+//   3) If we pre-create a ServiceWorkerProviderHost for this navigation, its
+//   ownershipped is passed to the ServiceWorkerNavigationHandleCore. The
+//   ServiceWorkerNavigationHandleCore id is updated.
+//
+//   4) The ServiceWorkerNavigationHandleCore informs the
+//   ServiceWorkerNavigationHandle on the UI that the service worker provider
+//   id was updated.

[michaeln, 2015/10/20 22:12:53]

Q: Is it possible for the navigation to commit on the UI thread prior to receipt
of the precreated host id? Is there a race there or does something gaurantee
this id will make it to the UI thread prior to commit msg being sent?

If that is a potential problem, we could coin the id on the UI thread.

[clamy, 2015/10/21 16:33:48]

No. The task will be posted when we create the ServiceWorkerResourceHandler, so
before the URLRequest was started. Therefore it cannot have committed yet.

+//
+//   5) When the navigation is ready to commit, the NavigationRequest will
+//   update the RequestNavigationParams based on the id from the
+//   ServiceWorkerNavigationHandle.
+//
+//   6) If the commit leads to the creation of a ServiceWorkerNetworkProvider
+//   in the renderer, a ServiceWorkerHostMsg_ProviderCreated will be received
+//   in the browser. The ServiceWorkerDispatcherHost will retrieve the
+//   ServiceWorkerProviderHost from the ServiceWorkerNavigationHandleCore and
+//   put it in the ServiceWorkerContextCore map of ServiceWorkerProviderHosts.
+//
+//   7) When the navigation finishes, the ServiceWorkerNavigationHandle is
+//   destroyed. The destructor of the ServiceWorkerNavigationHandle posts a
+//   task to destroy the ServiceWorkerNavigationHandleCore on the IO thread.
+//   This in turn leads to the destruction of an unclaimed
+//   ServiceWorkerProviderHost.
+class ServiceWorkerNavigationHandle {
+ public:
+  explicit ServiceWorkerNavigationHandle(
+      ServiceWorkerContextWrapper* context_wrapper);
+  ~ServiceWorkerNavigationHandle();
+
+  int service_worker_provider_host_id() const {
+    return service_worker_provider_host_id_;
+  }
+  ServiceWorkerNavigationHandleCore* core() const { return core_; }
+
+  // Called after a ServiceWorkerProviderHost with id
+  // |service_worker_provider_host_id| was pre-created for the navigation on the
+  // IO thread.
+  void DidCreateServiceWorkerProviderHost(int service_worker_provider_host_id);
+
+ private:
+  int service_worker_provider_host_id_;
+  ServiceWorkerNavigationHandleCore* core_;
+  base::WeakPtrFactory<ServiceWorkerNavigationHandle> weak_factory_;
+  DISALLOW_COPY_AND_ASSIGN(ServiceWorkerNavigationHandle);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_NAVIGATION_HANDLE_H_