Add a partial Mojo serial connection interface and implementation.

device/serial/serial.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 18 matching lines @@
       ],
       'dependencies': [
         '../../mojo/mojo.gyp:mojo_cpp_bindings',
         '../../net/net.gyp:net',
       ],
       'export_dependent_settings': [
         '../../mojo/mojo.gyp:mojo_cpp_bindings',
       ],
       'sources': [
         'serial.mojom',
+        'serial_connection.cc',
+        'serial_connection.h',
+        'serial_connection_factory.cc',
+        'serial_connection_factory.h',
         'serial_device_enumerator.cc',
         'serial_device_enumerator.h',
         'serial_device_enumerator_linux.cc',
         'serial_device_enumerator_linux.h',
         'serial_device_enumerator_mac.cc',
         'serial_device_enumerator_mac.h',
         'serial_device_enumerator_win.cc',
         'serial_device_enumerator_win.h',
         'serial_io_handler.cc',
         'serial_io_handler.h',
         'serial_io_handler_posix.cc',
         'serial_io_handler_posix.h',
         'serial_io_handler_win.cc',
         'serial_io_handler_win.h',
         'serial_service_impl.cc',
         'serial_service_impl.h',
       ],
     },
+    {
+      # GN version: //device/serial:test_util
+      'target_name': 'device_serial_test_util',
+      'type': 'static_library',
+      'dependencies': [
+        'device_serial',
+      ],
+      'sources': [
+        'test_serial_io_handler.cc',
+        'test_serial_io_handler.h',
+      ],
+    },
   ],
 }