Moved video stub implementation to RectangleUpdateDecoder.

Review URL: https://chromiumcodereview.appspot.com/10867039

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@153305 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 206 insertions, 175 deletions

diff --git a/remoting/client/chromoting_client.cc b/remoting/client/chromoting_client.cc
index 7c05d83..3bdc7b6 100644
--- a/remoting/client/chromoting_client.cc
+++ b/remoting/client/chromoting_client.cc
@@ -22,14 +22,6 @@ namespace remoting {
 
 using protocol::AuthenticationMethod;
 
-ChromotingClient::QueuedVideoPacket::QueuedVideoPacket(
-    scoped_ptr<VideoPacket> packet, const base::Closure& done)
-    : packet(packet.release()), done(done) {
-}
-
-ChromotingClient::QueuedVideoPacket::~QueuedVideoPacket() {
-}
-
 ChromotingClient::ChromotingClient(
     const ClientConfig& config,
     ClientContext* client_context,
@@ -42,8 +34,6 @@ ChromotingClient::ChromotingClient(
       connection_(connection),
       user_interface_(user_interface),
       rectangle_decoder_(rectangle_decoder),
-      packet_being_processed_(false),
-      last_sequence_number_(0),
       weak_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)) {
   audio_decode_scheduler_.reset(new AudioDecodeScheduler(
       client_context->main_task_runner(),
@@ -69,7 +59,8 @@ void ChromotingClient::Start(
 
   connection_->Connect(xmpp_proxy, config_.local_jid, config_.host_jid,
                        config_.host_public_key, transport_factory.Pass(),
-                       authenticator.Pass(), this, this, this, this,
+                       authenticator.Pass(), this, this, this,
+                       rectangle_decoder_,
                        audio_decode_scheduler_.get());
 }
 
@@ -77,11 +68,7 @@ void ChromotingClient::Stop(const base::Closure& shutdown_task) {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
   // Drop all pending packets.
-  while(!received_packets_.empty()) {
-    delete received_packets_.front().packet;
-    received_packets_.front().done.Run();
-    received_packets_.pop_front();
-  }
+  rectangle_decoder_->DropAllPackets();
 
   connection_->Disconnect(base::Bind(&ChromotingClient::OnDisconnected,
                                      weak_ptr_, shutdown_task));
@@ -93,7 +80,7 @@ void ChromotingClient::OnDisconnected(const base::Closure& shutdown_task) {
 
 ChromotingStats* ChromotingClient::GetStats() {
   DCHECK(task_runner_->BelongsToCurrentThread());
-  return &stats_;
+  return rectangle_decoder_->GetStats();
 }
 
 void ChromotingClient::InjectClipboardEvent(
@@ -107,70 +94,6 @@ void ChromotingClient::SetCursorShape(
   user_interface_->GetCursorShapeStub()->SetCursorShape(cursor_shape);
 }
 
-void ChromotingClient::ProcessVideoPacket(scoped_ptr<VideoPacket> packet,
-                                          const base::Closure& done) {
-  DCHECK(task_runner_->BelongsToCurrentThread());
-
-  // If the video packet is empty then drop it. Empty packets are used to
-  // maintain activity on the network.
-  if (!packet->has_data() || packet->data().size() == 0) {
-    done.Run();
-    return;
-  }
-
-  // Add one frame to the counter.
-  stats_.video_frame_rate()->Record(1);
-
-  // Record other statistics received from host.
-  stats_.video_bandwidth()->Record(packet->data().size());
-  if (packet->has_capture_time_ms())
-    stats_.video_capture_ms()->Record(packet->capture_time_ms());
-  if (packet->has_encode_time_ms())
-    stats_.video_encode_ms()->Record(packet->encode_time_ms());
-  if (packet->has_client_sequence_number() &&
-      packet->client_sequence_number() > last_sequence_number_) {
-    last_sequence_number_ = packet->client_sequence_number();
-    base::TimeDelta round_trip_latency =
-        base::Time::Now() -
-        base::Time::FromInternalValue(packet->client_sequence_number());
-    stats_.round_trip_ms()->Record(round_trip_latency.InMilliseconds());
-  }
-
-  received_packets_.push_back(QueuedVideoPacket(packet.Pass(), done));
-  if (!packet_being_processed_)
-    DispatchPacket();
-}
-
-int ChromotingClient::GetPendingVideoPackets() {
-  DCHECK(task_runner_->BelongsToCurrentThread());
-  return received_packets_.size();
-}
-
-void ChromotingClient::DispatchPacket() {
-  DCHECK(task_runner_->BelongsToCurrentThread());
-  CHECK(!packet_being_processed_);
-
-  if (received_packets_.empty()) {
-    // Nothing to do!
-    return;
-  }
-
-  scoped_ptr<VideoPacket> packet(received_packets_.front().packet);
-  received_packets_.front().packet = NULL;
-  packet_being_processed_ = true;
-
-  // Measure the latency between the last packet being received and presented.
-  bool last_packet = (packet->flags() & VideoPacket::LAST_PACKET) != 0;
-  base::Time decode_start;
-  if (last_packet)
-    decode_start = base::Time::Now();
-
-  rectangle_decoder_->DecodePacket(
-      packet.Pass(),
-      base::Bind(&ChromotingClient::OnPacketDone, base::Unretained(this),
-                 last_packet, decode_start));
-}
-
 void ChromotingClient::OnConnectionState(
     protocol::ConnectionToHost::State state,
     protocol::ErrorCode error) {
@@ -186,31 +109,6 @@ void ChromotingClient::OnConnectionReady(bool ready) {
   user_interface_->OnConnectionReady(ready);
 }
 
-void ChromotingClient::OnPacketDone(bool last_packet,
-                                    base::Time decode_start) {
-  if (!task_runner_->BelongsToCurrentThread()) {
-    task_runner_->PostTask(FROM_HERE, base::Bind(
-        &ChromotingClient::OnPacketDone, base::Unretained(this),
-        last_packet, decode_start));
-    return;
-  }
-
-  // Record the latency between the final packet being received and
-  // presented.
-  if (last_packet) {
-    stats_.video_decode_ms()->Record(
-        (base::Time::Now() - decode_start).InMilliseconds());
-  }
-
-  received_packets_.front().done.Run();
-  received_packets_.pop_front();
-
-  packet_being_processed_ = false;
-
-  // Process the next video packet.
-  DispatchPacket();
-}
-
 void ChromotingClient::Initialize() {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
diff --git a/remoting/client/chromoting_client.h b/remoting/client/chromoting_client.h
index f2355f1..f826394 100644
--- a/remoting/client/chromoting_client.h
+++ b/remoting/client/chromoting_client.h
@@ -38,10 +38,8 @@ class ClientContext;
 class ClientUserInterface;
 class RectangleUpdateDecoder;
 
-// TODO(sergeyu): Move VideoStub implementation to RectangleUpdateDecoder.
 class ChromotingClient : public protocol::ConnectionToHost::HostEventCallback,
-                         public protocol::ClientStub,
-                         public protocol::VideoStub {
+                         public protocol::ClientStub {
  public:
   // Objects passed in are not owned by this class.
   ChromotingClient(const ClientConfig& config,
@@ -75,32 +73,10 @@ class ChromotingClient : public protocol::ConnectionToHost::HostEventCallback,
       protocol::ErrorCode error) OVERRIDE;
   virtual void OnConnectionReady(bool ready) OVERRIDE;
 
-  // VideoStub implementation.
-  virtual void ProcessVideoPacket(scoped_ptr<VideoPacket> packet,
-                                  const base::Closure& done) OVERRIDE;
-  virtual int GetPendingVideoPackets() OVERRIDE;
-
  private:
-  struct QueuedVideoPacket {
-    QueuedVideoPacket(scoped_ptr<VideoPacket> packet,
-                      const base::Closure& done);
-    ~QueuedVideoPacket();
-    VideoPacket* packet;
-    base::Closure done;
-  };
-
   // Initializes connection.
   void Initialize();
 
-  // If a packet is not being processed, dispatches a single message from the
-  // |received_packets_| queue.
-  void DispatchPacket();
-
-  // Callback method when a VideoPacket is processed.
-  // If |last_packet| is true then |decode_start| contains the timestamp when
-  // the packet will start to be processed.
-  void OnPacketDone(bool last_packet, base::Time decode_start);
-
   void OnDisconnected(const base::Closure& shutdown_task);
 
   // The following are not owned by this class.
@@ -116,22 +92,9 @@ class ChromotingClient : public protocol::ConnectionToHost::HostEventCallback,
   // If non-NULL, this is called when the client is done.
   base::Closure client_done_;
 
-  // Contains all video packets that have been received, but have not yet been
-  // processed.
-  //
-  // Used to serialize sending of messages to the client.
-  std::list<QueuedVideoPacket> received_packets_;
-
-  // True if a message is being processed. Can be used to determine if it is
-  // safe to dispatch another message.
-  bool packet_being_processed_;
-
   // Record the statistics of the connection.
   ChromotingStats stats_;
 
-  // Keep track of the last sequence number bounced back from the host.
-  int64 last_sequence_number_;
-
   // WeakPtr used to avoid tasks accessing the client after it is deleted.
   base::WeakPtrFactory<ChromotingClient> weak_factory_;
   base::WeakPtr<ChromotingClient> weak_ptr_;
diff --git a/remoting/client/plugin/chromoting_instance.cc b/remoting/client/plugin/chromoting_instance.cc
index f4be000..a28a8e9 100644
--- a/remoting/client/plugin/chromoting_instance.cc
+++ b/remoting/client/plugin/chromoting_instance.cc
@@ -232,8 +232,9 @@ bool ChromotingInstance::Init(uint32_t argc,
   // PepperView with a ref-counted proxy object.
   scoped_refptr<FrameConsumerProxy> consumer_proxy =
       new FrameConsumerProxy(plugin_task_runner_);
-  rectangle_decoder_ = new RectangleUpdateDecoder(
-      context_.decode_task_runner(), consumer_proxy);
+  rectangle_decoder_ = new RectangleUpdateDecoder(context_.main_task_runner(),
+                                                  context_.decode_task_runner(),
+                                                  consumer_proxy);
   view_.reset(new PepperView(this, &context_, rectangle_decoder_.get()));
   consumer_proxy->Attach(view_->AsWeakPtr());
 
diff --git a/remoting/client/rectangle_update_decoder.cc b/remoting/client/rectangle_update_decoder.cc
index 0fb253b..c7a1404 100644
--- a/remoting/client/rectangle_update_decoder.cc
+++ b/remoting/client/rectangle_update_decoder.cc
@@ -6,7 +6,6 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
-#include "base/callback.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/message_loop_proxy.h"
@@ -24,16 +23,30 @@ using remoting::protocol::SessionConfig;
 
 namespace remoting {
 
+RectangleUpdateDecoder::QueuedVideoPacket::QueuedVideoPacket(
+    scoped_ptr<VideoPacket> packet,
+    const base::Closure& done)
+    : packet(packet.release()),
+      done(done) {
+}
+
+RectangleUpdateDecoder::QueuedVideoPacket::~QueuedVideoPacket() {
+}
+
 RectangleUpdateDecoder::RectangleUpdateDecoder(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+    scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
+    scoped_refptr<base::SingleThreadTaskRunner> decode_task_runner,
     scoped_refptr<FrameConsumerProxy> consumer)
-    : task_runner_(task_runner),
+    : main_task_runner_(main_task_runner),
+      decode_task_runner_(decode_task_runner),
       consumer_(consumer),
       source_size_(SkISize::Make(0, 0)),
       source_dpi_(SkIPoint::Make(0, 0)),
       view_size_(SkISize::Make(0, 0)),
       clip_area_(SkIRect::MakeEmpty()),
-      paint_scheduled_(false) {
+      paint_scheduled_(false),
+      packet_being_processed_(false),
+      latest_sequence_number_(0) {
 }
 
 RectangleUpdateDecoder::~RectangleUpdateDecoder() {
@@ -55,12 +68,7 @@ void RectangleUpdateDecoder::Initialize(const SessionConfig& config) {
 
 void RectangleUpdateDecoder::DecodePacket(scoped_ptr<VideoPacket> packet,
                                           const base::Closure& done) {
-  if (!task_runner_->BelongsToCurrentThread()) {
-    task_runner_->PostTask(
-        FROM_HERE, base::Bind(&RectangleUpdateDecoder::DecodePacket,
-                              this, base::Passed(&packet), done));
-    return;
-  }
+  DCHECK(decode_task_runner_->BelongsToCurrentThread());
 
   base::ScopedClosureRunner done_runner(done);
   bool decoder_needs_reset = false;
@@ -109,7 +117,7 @@ void RectangleUpdateDecoder::SchedulePaint() {
   if (paint_scheduled_)
     return;
   paint_scheduled_ = true;
-  task_runner_->PostTask(
+  decode_task_runner_->PostTask(
       FROM_HERE, base::Bind(&RectangleUpdateDecoder::DoPaint, this));
 }
 
@@ -141,8 +149,8 @@ void RectangleUpdateDecoder::DoPaint() {
 }
 
 void RectangleUpdateDecoder::RequestReturnBuffers(const base::Closure& done) {
-  if (!task_runner_->BelongsToCurrentThread()) {
-    task_runner_->PostTask(
+  if (!decode_task_runner_->BelongsToCurrentThread()) {
+    decode_task_runner_->PostTask(
         FROM_HERE, base::Bind(&RectangleUpdateDecoder::RequestReturnBuffers,
         this, done));
     return;
@@ -158,8 +166,8 @@ void RectangleUpdateDecoder::RequestReturnBuffers(const base::Closure& done) {
 }
 
 void RectangleUpdateDecoder::DrawBuffer(pp::ImageData* buffer) {
-  if (!task_runner_->BelongsToCurrentThread()) {
-    task_runner_->PostTask(
+  if (!decode_task_runner_->BelongsToCurrentThread()) {
+    decode_task_runner_->PostTask(
         FROM_HERE, base::Bind(&RectangleUpdateDecoder::DrawBuffer,
                               this, buffer));
     return;
@@ -173,8 +181,8 @@ void RectangleUpdateDecoder::DrawBuffer(pp::ImageData* buffer) {
 }
 
 void RectangleUpdateDecoder::InvalidateRegion(const SkRegion& region) {
-  if (!task_runner_->BelongsToCurrentThread()) {
-    task_runner_->PostTask(
+  if (!decode_task_runner_->BelongsToCurrentThread()) {
+    decode_task_runner_->PostTask(
         FROM_HERE, base::Bind(&RectangleUpdateDecoder::InvalidateRegion,
                               this, region));
     return;
@@ -188,8 +196,8 @@ void RectangleUpdateDecoder::InvalidateRegion(const SkRegion& region) {
 
 void RectangleUpdateDecoder::SetOutputSizeAndClip(const SkISize& view_size,
                                                   const SkIRect& clip_area) {
-  if (!task_runner_->BelongsToCurrentThread()) {
-    task_runner_->PostTask(
+  if (!decode_task_runner_->BelongsToCurrentThread()) {
+    decode_task_runner_->PostTask(
         FROM_HERE, base::Bind(&RectangleUpdateDecoder::SetOutputSizeAndClip,
                               this, view_size, clip_area));
     return;
@@ -225,4 +233,112 @@ void RectangleUpdateDecoder::SetOutputSizeAndClip(const SkISize& view_size,
   }
 }
 
+void RectangleUpdateDecoder::ProcessVideoPacket(scoped_ptr<VideoPacket> packet,
+                                                const base::Closure& done) {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+
+  // If the video packet is empty then drop it. Empty packets are used to
+  // maintain activity on the network.
+  if (!packet->has_data() || packet->data().size() == 0) {
+    done.Run();
+    return;
+  }
+
+  // Add one frame to the counter.
+  stats_.video_frame_rate()->Record(1);
+
+  // Record other statistics received from host.
+  stats_.video_bandwidth()->Record(packet->data().size());
+  if (packet->has_capture_time_ms())
+    stats_.video_capture_ms()->Record(packet->capture_time_ms());
+  if (packet->has_encode_time_ms())
+    stats_.video_encode_ms()->Record(packet->encode_time_ms());
+  if (packet->has_client_sequence_number() &&
+      packet->client_sequence_number() > latest_sequence_number_) {
+    latest_sequence_number_ = packet->client_sequence_number();
+    base::TimeDelta round_trip_latency =
+        base::Time::Now() -
+        base::Time::FromInternalValue(packet->client_sequence_number());
+    stats_.round_trip_ms()->Record(round_trip_latency.InMilliseconds());
+  }
+
+  received_packets_.push_back(QueuedVideoPacket(packet.Pass(), done));
+  if (!packet_being_processed_)
+    ProcessNextPacket();
+}
+
+int RectangleUpdateDecoder::GetPendingVideoPackets() {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+  return received_packets_.size();
+}
+
+void RectangleUpdateDecoder::DropAllPackets() {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+
+  while(!received_packets_.empty()) {
+    delete received_packets_.front().packet;
+    received_packets_.front().done.Run();
+    received_packets_.pop_front();
+  }
+}
+
+void RectangleUpdateDecoder::ProcessNextPacket() {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+  CHECK(!packet_being_processed_);
+
+  if (received_packets_.empty()) {
+    // Nothing to do!
+    return;
+  }
+
+  scoped_ptr<VideoPacket> packet(received_packets_.front().packet);
+  received_packets_.front().packet = NULL;
+  packet_being_processed_ = true;
+
+  // Measure the latency between the last packet being received and presented.
+  bool last_packet = (packet->flags() & VideoPacket::LAST_PACKET) != 0;
+  base::Time decode_start;
+  if (last_packet)
+    decode_start = base::Time::Now();
+
+  base::Closure callback = base::Bind(&RectangleUpdateDecoder::OnPacketDone,
+                                      this,
+                                      last_packet,
+                                      decode_start);
+
+  decode_task_runner_->PostTask(FROM_HERE, base::Bind(
+      &RectangleUpdateDecoder::DecodePacket, this,
+      base::Passed(&packet), callback));
+}
+
+void RectangleUpdateDecoder::OnPacketDone(bool last_packet,
+                                          base::Time decode_start) {
+  if (!main_task_runner_->BelongsToCurrentThread()) {
+    main_task_runner_->PostTask(FROM_HERE, base::Bind(
+        &RectangleUpdateDecoder::OnPacketDone, this,
+        last_packet, decode_start));
+    return;
+  }
+
+  // Record the latency between the final packet being received and
+  // presented.
+  if (last_packet) {
+    stats_.video_decode_ms()->Record(
+        (base::Time::Now() - decode_start).InMilliseconds());
+  }
+
+  received_packets_.front().done.Run();
+  received_packets_.pop_front();
+
+  packet_being_processed_ = false;
+
+  // Process the next video packet.
+  ProcessNextPacket();
+}
+
+ChromotingStats* RectangleUpdateDecoder::GetStats() {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+  return &stats_;
+}
+
 }  // namespace remoting
diff --git a/remoting/client/rectangle_update_decoder.h b/remoting/client/rectangle_update_decoder.h
index 3d61b97..af91267 100644
--- a/remoting/client/rectangle_update_decoder.h
+++ b/remoting/client/rectangle_update_decoder.h
@@ -7,12 +7,14 @@
 
 #include <list>
 
-#include "base/callback_forward.h"
+#include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "remoting/codec/video_decoder.h"
+#include "remoting/client/chromoting_stats.h"
 #include "remoting/client/frame_consumer_proxy.h"
 #include "remoting/client/frame_producer.h"
+#include "remoting/protocol/video_stub.h"
 
 namespace base {
 class SingleThreadTaskRunner;
@@ -24,6 +26,7 @@ class ImageData;
 
 namespace remoting {
 
+class ChromotingStats;
 class VideoPacket;
 
 namespace protocol {
@@ -35,21 +38,24 @@ class SessionConfig;
 // TODO(sergeyu): Rename this class.
 class RectangleUpdateDecoder
     : public base::RefCountedThreadSafe<RectangleUpdateDecoder>,
-      public FrameProducer {
+      public FrameProducer,
+      public protocol::VideoStub {
  public:
-  // Creates an update decoder on |task_runner_|, outputting to |consumer|.
+  // Creates an update decoder on |main_task_runner_| and |decode_task_runner_|,
+  // outputting to |consumer|. The |main_task_runner_| is responsible for
+  // receiving and queueing packets. The |decode_task_runner_| is responsible
+  // for decoding the video packets.
   // TODO(wez): Replace the ref-counted proxy with an owned FrameConsumer.
   RectangleUpdateDecoder(
-      scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+      scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
+      scoped_refptr<base::SingleThreadTaskRunner> decode_task_runner,
       scoped_refptr<FrameConsumerProxy> consumer);
 
   // Initializes decoder with the information from the protocol config.
   void Initialize(const protocol::SessionConfig& config);
 
-  // Decodes the contents of |packet|. DecodePacket may keep a reference to
-  // |packet| so the |packet| must remain alive and valid until |done| is
-  // executed.
-  void DecodePacket(scoped_ptr<VideoPacket> packet, const base::Closure& done);
+  // Removes all video packets in the queue.
+  void DropAllPackets();
 
   // FrameProducer implementation.  These methods may be called before we are
   // Initialize()d, or we know the source screen size.
@@ -59,7 +65,23 @@ class RectangleUpdateDecoder
   virtual void SetOutputSizeAndClip(const SkISize& view_size,
                                     const SkIRect& clip_area) OVERRIDE;
 
+  // VideoStub implementation.
+  virtual void ProcessVideoPacket(scoped_ptr<VideoPacket> packet,
+                                  const base::Closure& done) OVERRIDE;
+  virtual int GetPendingVideoPackets() OVERRIDE;
+
+  // Return the stats recorded by this client.
+  ChromotingStats* GetStats();
+
  private:
+  struct QueuedVideoPacket {
+    QueuedVideoPacket(scoped_ptr<VideoPacket> packet,
+                      const base::Closure& done);
+    ~QueuedVideoPacket();
+    VideoPacket* packet;
+    base::Closure done;
+  };
+
   friend class base::RefCountedThreadSafe<RectangleUpdateDecoder>;
   virtual ~RectangleUpdateDecoder();
 
@@ -68,7 +90,22 @@ class RectangleUpdateDecoder
   void SchedulePaint();
   void DoPaint();
 
-  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+  // If a packet is not being processed, dispatches a single message from the
+  // |received_packets_| queue.
+  void ProcessNextPacket();
+
+  // Decodes the contents of |packet|. DecodePacket may keep a reference to
+  // |packet| so the |packet| must remain alive and valid until |done| is
+  // executed.
+  void DecodePacket(scoped_ptr<VideoPacket> packet, const base::Closure& done);
+
+  // Callback method when a VideoPacket is processed.
+  // If |last_packet| is true then |decode_start| contains the timestamp when
+  // the packet will start to be processed.
+  void OnPacketDone(bool last_packet, base::Time decode_start);
+
+  scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
+  scoped_refptr<base::SingleThreadTaskRunner> decode_task_runner_;
   scoped_refptr<FrameConsumerProxy> consumer_;
   scoped_ptr<VideoDecoder> decoder_;
 
@@ -78,7 +115,7 @@ class RectangleUpdateDecoder
   // Vertical and horizontal DPI of the remote screen.
   SkIPoint source_dpi_;
 
-  // The current dimentions of the frame consumer view.
+  // The current dimensions of the frame consumer view.
   SkISize view_size_;
   SkIRect clip_area_;
 
@@ -87,6 +124,22 @@ class RectangleUpdateDecoder
 
   // Flag used to coalesce runs of SchedulePaint()s into a single DoPaint().
   bool paint_scheduled_;
+
+  // Contains all video packets that have been received, but have not yet been
+  // processed.
+  //
+  // Used to serialize sending of messages to the client.
+  // TODO(sergeyu): Simplify this code and remove this list.
+  std::list<QueuedVideoPacket> received_packets_;
+
+  // True if a message is being processed. Can be used to determine if it is
+  // safe to dispatch another message.
+  bool packet_being_processed_;
+
+  ChromotingStats stats_;
+
+  // Keep track of the most recent sequence number bounced back from the host.
+  int64 latest_sequence_number_;
 };
 
 }  // namespace remoting