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

device/serial/serial.mojom

 // 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.
 
+import "data_stream.mojom"
+
 module device.serial {
 
 struct DeviceInfo {
   string? path;
   uint16 vendor_id;
   bool has_vendor_id = false;
   uint16 product_id;
   bool has_product_id = false;
   string? display_name;
 };
@@ skipping 61 matching lines @@
   bool dcd;
   bool cts;
   bool ri;
   bool dsr;
 };
 
 interface SerialService {
   GetDevices() => (DeviceInfo?[]? devices);
 
   // Creates a |Connection| to |path| with options specified by |options|,
-  // returning it via |connection|. This will fail and |connection| will not be
-  // usable if |path| does not specify a valid serial device or there is an
-  // error connecting to or configuring the connection.
+  // returning it via |connection|. Sending and receiving data over this
+  // connection is handled by |sink| and |source|, respectively. This will fail
+  // and |connection| will not be usable if |path| does not specify a valid
+  // serial device or there is an error connecting to or configuring the
+  // connection.
   Connect(string? path,
           ConnectionOptions? options,
-          Connection&? connection);
+          Connection&? connection,
+          DataSink&? sink,
+          DataSource&? source);
 };
 
 interface Connection {
   GetInfo() => (ConnectionInfo? info);
   SetOptions(ConnectionOptions? options) => (bool success);
   SetControlSignals(HostControlSignals? signals) => (bool success);
   GetControlSignals() => (DeviceControlSignals? signals);
   Flush() => (bool success);
 };
 
 }