Implement the host side of serial connection I/O on data pipe.

device/serial/serial_connection.h

Index: device/serial/serial_connection.h
diff --git a/device/serial/serial_connection.h b/device/serial/serial_connection.h
index 31d5fc3a894cbdac3a2b90e43d9000b31c9d155c..807e173700f6ae52870490b531a243376b7af98a 100644
--- a/device/serial/serial_connection.h
+++ b/device/serial/serial_connection.h
@@ -6,16 +6,23 @@
 #define DEVICE_SERIAL_SERIAL_CONNECTION_H_
 
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "device/serial/serial.mojom.h"
 #include "mojo/public/cpp/bindings/interface_impl.h"
 
 namespace device {
 
+class DataSinkReceiver;
+class DataSourceSender;
+class ReadOnlyBuffer;
 class SerialIoHandler;
+class WritableBuffer;
 
 class SerialConnection : public mojo::InterfaceImpl<serial::Connection> {
  public:
-  explicit SerialConnection(scoped_refptr<SerialIoHandler> io_handler);
+  SerialConnection(scoped_refptr<SerialIoHandler> io_handler,
+                   mojo::InterfaceRequest<serial::DataSink> sink,
+                   mojo::InterfaceRequest<serial::DataSource> source);
   virtual ~SerialConnection();
 
   // mojo::InterfaceImpl<serial::Connection> overrides.
@@ -31,7 +38,13 @@ class SerialConnection : public mojo::InterfaceImpl<serial::Connection> {
   virtual void Flush(const mojo::Callback<void(bool)>& callback) OVERRIDE;
 
  private:
+  void OnSendPipeReady(scoped_ptr<ReadOnlyBuffer> buffer);
+  void OnSendCancelled(int32_t error);
+  void OnReceivePipeReady(scoped_ptr<WritableBuffer> buffer);
+
   scoped_refptr<SerialIoHandler> io_handler_;
+  scoped_refptr<DataSinkReceiver> receiver_;
+  scoped_refptr<DataSourceSender> sender_;
 
   DISALLOW_COPY_AND_ASSIGN(SerialConnection);
 };