cros: Move DemoModeDetector out of webui directory.

chrome/browser/chromeos/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("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//extensions/features/features.gni")
 import("//media/media_options.gni")
 import("//printing/features/features.gni")
 import("//third_party/protobuf/proto_library.gni")
@@ skipping 665 matching lines @@
     "login/auth/auth_prewarmer.cc",
     "login/auth/auth_prewarmer.h",
     "login/auth/chrome_cryptohome_authenticator.cc",
     "login/auth/chrome_cryptohome_authenticator.h",
     "login/auth/chrome_login_performer.cc",
     "login/auth/chrome_login_performer.h",
     "login/chrome_restart_request.cc",
     "login/chrome_restart_request.h",
     "login/demo_mode/demo_app_launcher.cc",
     "login/demo_mode/demo_app_launcher.h",
+    "login/demo_mode/demo_mode_detector.cc",
+    "login/demo_mode/demo_mode_detector.h",
     "login/easy_unlock/bootstrap_manager.cc",
     "login/easy_unlock/bootstrap_manager.h",
     "login/easy_unlock/bootstrap_user_context_initializer.cc",
     "login/easy_unlock/bootstrap_user_context_initializer.h",
     "login/easy_unlock/bootstrap_user_flow.cc",
     "login/easy_unlock/bootstrap_user_flow.h",
     "login/easy_unlock/easy_unlock_challenge_wrapper.cc",
     "login/easy_unlock/easy_unlock_challenge_wrapper.h",
     "login/easy_unlock/easy_unlock_create_keys_operation.cc",
     "login/easy_unlock/easy_unlock_create_keys_operation.h",
@@ skipping 1070 matching lines @@
     "policy/proto/chrome_device_policy.proto",
     "policy/proto/install_attributes.proto",
   ]
 }
 
 proto_library("attestation_proto") {
   sources = [
     "attestation/attestation_key_payload.proto",
   ]
 }