[ios] Adds code to support the iOS Handoff feature.

ios/chrome/browser/BUILD.gn

 # Copyright 2015 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("//build/config/features.gni")
 import("//third_party/protobuf/proto_library.gni")
 
 declare_args() {
   google_test_gaia_client_id = ""
   google_test_gaia_client_secret = ""
@@ skipping 59 matching lines @@
     "web_data_service_factory.cc",
     "web_data_service_factory.h",
     "xcallback_parameters.h",
     "xcallback_parameters.mm",
   ]
   deps = [
     "//base",
     "//components/autofill/core/browser",
     "//components/autofill/core/common",
     "//components/gcm_driver",
+    "//components/handoff",
     "//components/keyed_service/core",
     "//components/keyed_service/ios",
     "//components/metrics",
     "//components/metrics_services_manager",
     "//components/net_log",
     "//components/network_session_configurator",
     "//components/pref_registry",
     "//components/prefs",
     "//components/proxy_config",
     "//components/search_engines",
@@ skipping 138 matching lines @@
     "//components/proxy_config",
     "//components/ssl_config",
     "//components/variations",
     "//ios/web:test_support",
     "//net",
     "//net:test_support",
     "//testing/gtest",
     "//url",
   ]
 }