Revert of [cast_channel] Move cast_channel related files from //extensions to //components

components/cast_channel/keep_alive_delegate.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 COMPONENTS_CAST_CHANNEL_KEEP_ALIVE_DELEGATE_H_
-#define COMPONENTS_CAST_CHANNEL_KEEP_ALIVE_DELEGATE_H_
-
-#include "base/macros.h"
-#include "base/threading/thread_checker.h"
-#include "base/timer/timer.h"
-#include "components/cast_channel/cast_transport.h"
-#include "components/cast_channel/proto/cast_channel.pb.h"
-
-namespace cast_channel {
-
-class CastSocket;
-class Logger;
-
-// Decorator delegate which provides keep-alive functionality.
-// Keep-alive messages are handled by this object; all other messages and
-// errors are passed to |inner_delegate_|.
-class KeepAliveDelegate : public CastTransport::Delegate {
- public:
-  // |socket|: The socket to be kept alive.
-  // |logger|: The logging object which collects protocol events and error
-  //           details.
-  // |inner_delegate|: The delegate which processes all non-keep-alive
-  //                   messages. This object assumes ownership of
-  //                   |inner_delegate|.
-  // |ping_interval|: The amount of idle time to wait before sending a PING to
-  //                  the remote end.
-  // |liveness_timeout|: The amount of idle time to wait before terminating the
-  //                     connection.
-  KeepAliveDelegate(CastSocket* socket,
-                    scoped_refptr<Logger> logger,
-                    std::unique_ptr<CastTransport::Delegate> inner_delegate,
-                    base::TimeDelta ping_interval,
-                    base::TimeDelta liveness_timeout);
-
-  ~KeepAliveDelegate() override;
-
-  // Creates a keep-alive message (e.g. PING or PONG).
-  static CastMessage CreateKeepAliveMessage(const char* message_type);
-
-  void SetTimersForTest(std::unique_ptr<base::Timer> injected_ping_timer,
-                        std::unique_ptr<base::Timer> injected_liveness_timer);
-
-  // CastTransport::Delegate implementation.
-  void Start() override;
-  void OnError(ChannelError error_state) override;
-  void OnMessage(const CastMessage& message) override;
-
-  static const char kHeartbeatPingType[];
-  static const char kHeartbeatPongType[];
-
- private:
-  // Restarts the ping/liveness timeout timers. Called when a message
-  // is received from the remote end.
-  void ResetTimers();
-
-  // Sends a formatted PING or PONG message to the remote side.
-  void SendKeepAliveMessage(const CastMessage& message,
-                            const char* message_type);
-
-  // Callback for SendKeepAliveMessage.
-  void SendKeepAliveMessageComplete(const char* message_type, int rv);
-
-  // Called when the liveness timer expires, indicating that the remote
-  // end has not responded within the |liveness_timeout_| interval.
-  void LivenessTimeout();
-
-  // Stops the ping and liveness timers if they are started.
-  // To be called after an error.
-  void Stop();
-
-  // Indicates that Start() was called.
-  bool started_;
-
-  // Socket that is managed by the keep-alive object.
-  CastSocket* socket_;
-
-  // Logging object.
-  scoped_refptr<Logger> logger_;
-
-  // Delegate object which receives all non-keep alive messages.
-  std::unique_ptr<CastTransport::Delegate> inner_delegate_;
-
-  // Amount of idle time to wait before disconnecting.
-  base::TimeDelta liveness_timeout_;
-
-  // Amount of idle time to wait before pinging the receiver.
-  base::TimeDelta ping_interval_;
-
-  // Fired when |ping_interval_| is exceeded or when triggered by test code.
-  std::unique_ptr<base::Timer> ping_timer_;
-
-  // Fired when |liveness_timer_| is exceeded.
-  std::unique_ptr<base::Timer> liveness_timer_;
-
-  // The PING message to send over the wire.
-  CastMessage ping_message_;
-
-  // The PONG message to send over the wire.
-  CastMessage pong_message_;
-
-  THREAD_CHECKER(thread_checker_);
-
-  DISALLOW_COPY_AND_ASSIGN(KeepAliveDelegate);
-};
-
-}  // namespace cast_channel
-
-#endif  // COMPONENTS_CAST_CHANNEL_KEEP_ALIVE_DELEGATE_H_