Add the JS data pipe client to be used to implement serial send.

extensions/BUILD.gn

 # 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("//tools/grit/grit_rule.gni")
 import("//tools/grit/repack.gni")
 
 # GYP version: extensions/extensions_resources.gyp:extensions_resources
 group("extensions_resources") {
   deps = [
@@ skipping 123 matching lines @@
     "browser/process_manager_unittest.cc",
     "common/api/sockets/sockets_manifest_permission_unittest.cc",
     "common/csp_validator_unittest.cc",
     "common/event_filter_unittest.cc",
     "common/id_util_unittest.cc",
     "common/one_shot_event_unittest.cc",
     "common/permissions/manifest_permission_set_unittest.cc",
     "common/user_script_unittest.cc",
     "renderer/activity_log_converter_strategy_unittest.cc",
     "renderer/api/serial/data_receiver_unittest.cc",
+    "renderer/api/serial/data_sender_unittest.cc",
     "renderer/api/serial/serial_api_unittest.cc",
     "renderer/api_test_base.cc",
     "renderer/api_test_base.h",
     "renderer/api_test_base_unittest.cc",
     "renderer/event_unittest.cc",
     "renderer/json_schema_unittest.cc",
     "renderer/messaging_utils_unittest.cc",
     "renderer/module_system_test.cc",
     "renderer/module_system_test.h",
     "renderer/module_system_unittest.cc",
@@ skipping 29 matching lines @@
     "//testing/gtest",
   ]
 
   if (is_win) {
     deps += [
       "//base/allocator",
     ]
   }
 }
 }