Move the serial API to extensions/.

extensions/common/api/api.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.
 
 {
   'targets': [
     {
       'target_name': 'extensions_api',
       'type': 'static_library',
       'sources': [
@@ skipping 10 matching lines @@
         'non_compiled_schema_files': [
         ],
         'conditions': [
           ['enable_extensions==1', {
             'schema_files': [
               'app_runtime.idl',
               'dns.idl',
               'extensions_manifest_types.json',
               'power.idl',
               'runtime.json',
+              'serial.idl',
               'socket.idl',
               'sockets_tcp.idl',
               'sockets_tcp_server.idl',
               'sockets_udp.idl',
               'storage.json',
               'test.json',
               'usb.idl',
             ],
           }, {
             # TODO: Eliminate these on Android. See crbug.com/305852.
             'schema_files': [
               'extensions_manifest_types.json',
               'runtime.json',
             ],
           }],
         ],
         'cc_dir': 'extensions/common/api',
         'root_namespace': 'extensions::core_api',
         'impl_dir': 'extensions/browser/api',
       },
       'dependencies': [
+        '<(DEPTH)/device/serial/serial.gyp:device_serial',
         '<(DEPTH)/skia/skia.gyp:skia',
       ],
     },
   ],
 }