Implement a RenderFrame-less path for Web Notifications.

content/child/notifications/notification_dispatcher.cc

+// Copyright 2014 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.
+
+#include "content/child/notifications/notification_dispatcher.h"
+
+#include "base/message_loop/message_loop_proxy.h"
+#include "content/child/notifications/notification_manager.h"
+#include "content/child/thread_safe_sender.h"
+#include "content/child/worker_thread_task_runner.h"
+#include "content/common/platform_notification_messages.h"
+
+namespace content {
+
+NotificationDispatcher::NotificationDispatcher(
+    ThreadSafeSender* thread_safe_sender)
+    : main_thread_loop_proxy_(base::MessageLoopProxy::current()),
+      thread_safe_sender_(thread_safe_sender) {
+}
+
+NotificationDispatcher::~NotificationDispatcher() {}
+
+int NotificationDispatcher::GenerateNotificationId(int thread_id) {
+  base::AutoLock lock(notification_id_map_lock_);
+  notification_id_map_[next_notification_id_] = thread_id;
+  return next_notification_id_++;
+}
+
+base::TaskRunner* NotificationDispatcher::OverrideTaskRunnerForMessage(
+    const IPC::Message& msg) {
+  if (!ShouldHandleMessage(msg))
+    return NULL;
+
+  int notification_id = -1,
+      thread_id = 0;
+
+  const bool success = PickleIterator(msg).ReadInt(&notification_id);
+  DCHECK(success);
+
+  {
+    base::AutoLock lock(notification_id_map_lock_);
+    auto iterator = notification_id_map_.find(notification_id);
+    if (iterator != notification_id_map_.end())
+      thread_id = iterator->second;
+  }
+
+  if (!thread_id)
+    return main_thread_loop_proxy_.get();
+
+  return new WorkerThreadTaskRunner(thread_id);
+}
+
+bool NotificationDispatcher::OnMessageReceived(const IPC::Message& msg) {
+  if (!ShouldHandleMessage(msg))
+    return false;
+
+  NotificationManager::ThreadSpecificInstance(thread_safe_sender_.get(), this)
+      ->OnMessageReceived(msg);
+  return true;
+}
+
+bool NotificationDispatcher::ShouldHandleMessage(const IPC::Message& msg) {
+  // The thread-safe message filter is responsible for handling all the messages
+  // except for the routed permission-request-completed message, which will be
+  // picked up by the RenderFrameImpl instead.
+  return IPC_MESSAGE_CLASS(msg) == PlatformNotificationMsgStart &&
+         msg.type() != PlatformNotificationMsg_PermissionRequestComplete::ID;
+}
+
+}  // namespace content