Delegate WebSocket message handlers to the loading task runner

content/child/websocket_message_filter.h

+// Copyright 2016 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_CHILD_WEBSOCKET_MESSAGE_FILTER_H_
+#define CONTENT_CHILD_WEBSOCKET_MESSAGE_FILTER_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
+#include "ipc/message_filter.h"
+
+namespace base {
+class SingleThreadTaskRunner;
+}
+
+namespace content {
+
+class WebSocketDispatcher;
+
+// Delegates IPC messages to a WebSocketDispatcher on the loading task queue
+// instead of the default task queue.
+class WebSocketMessageFilter : public IPC::MessageFilter {
+ public:
+  explicit WebSocketMessageFilter(WebSocketDispatcher* websocket_dispatcher);
+
+  // IPC::MessageFilter implementation.
+  bool OnMessageReceived(const IPC::Message& message) override;
+
+  void SetLoadingTaskRunner(
+      scoped_refptr<base::SingleThreadTaskRunner> loading_task_runner) {
+    loading_task_runner_ = loading_task_runner;
+  }
+
+ private:
+  ~WebSocketMessageFilter() override;
+  void OnMessageReceivedOnMainThread(const IPC::Message& message);
+
+  scoped_refptr<base::SingleThreadTaskRunner> loading_task_runner_;
+
+  // This actual object is owned by a ChildThreadImpl and is derefed only on the
+  // main thread.
+  base::WeakPtr<WebSocketDispatcher> websocket_dispatcher_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebSocketMessageFilter);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_CHILD_WEBSOCKET_MESSAGE_FILTER_H_