Revert of Remove Client= from device/serial/data_stream.mojom.

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.
 
 module device.serial;
 
 import "data_stream.mojom";
 
 struct DeviceInfo {
   string path;
@@ skipping 76 matching lines @@
   // Creates a |Connection| to |path| with options specified by |options|,
   // 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,
           DataSink& sink,
-          DataSinkClient sink_client,
-          DataSource& source,
-          DataSourceClient source_client);
+          DataSource& source);
 };
 
 interface Connection {
   GetInfo() => (ConnectionInfo? info);
   SetOptions(ConnectionOptions options) => (bool success);
   SetControlSignals(HostControlSignals signals) => (bool success);
   GetControlSignals() => (DeviceControlSignals? signals);
   Flush() => (bool success);
 };