Start the Physical Web scanner on Chrome start

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("//ios/web/js_compile.gni")
 import("//third_party/protobuf/proto_library.gni")
 
 declare_args() {
   google_test_gaia_client_id = ""
@@ skipping 302 matching lines @@
     "passwords/password_generation_offer_view.mm",
     "passwords/password_generation_prompt_delegate.h",
     "passwords/password_generation_utils.h",
     "passwords/password_generation_utils.mm",
     "passwords/passwords_ui_delegate.h",
     "passwords/update_password_infobar_controller.h",
     "passwords/update_password_infobar_controller.mm",
     "physical_web/create_physical_web_data_source.h",
     "physical_web/create_physical_web_data_source.mm",
     "physical_web/physical_web_constants.h",
+    "physical_web/start_physical_web_discovery.h",
+    "physical_web/start_physical_web_discovery.mm",
     "pref_names.cc",
     "pref_names.h",
     "prefs/browser_prefs.h",
     "prefs/browser_prefs.mm",
     "prefs/ios_chrome_pref_model_associator_client.cc",
     "prefs/ios_chrome_pref_model_associator_client.h",
     "prefs/ios_chrome_pref_service_factory.cc",
     "prefs/ios_chrome_pref_service_factory.h",
     "prefs/pref_observer_bridge.h",
     "prefs/pref_observer_bridge.mm",
@@ skipping 516 matching lines @@
     "//ios/public/provider/chrome/browser",
     "//ios/public/provider/chrome/browser:test_support",
     "//ios/web",
     "//net:test_support",
     "//testing/gmock",
     "//testing/gtest",
     "//ui/base",
     "//url",
   ]
 }