Introduce lock screen app manager

chrome/browser/chromeos/BUILD.gn

Index: chrome/browser/chromeos/BUILD.gn
diff --git a/chrome/browser/chromeos/BUILD.gn b/chrome/browser/chromeos/BUILD.gn
index 0074d39421f301c591b6e0a3d0becdbf3475cf64..acd04e6a0184b2aa9677c7b080fe2a43dcd63885 100644
--- a/chrome/browser/chromeos/BUILD.gn
+++ b/chrome/browser/chromeos/BUILD.gn
@@ -711,6 +711,9 @@ source_set("chromeos") {
     "launcher_search_provider/launcher_search_provider_service_factory.h",
     "locale_change_guard.cc",
     "locale_change_guard.h",
+    "lock_screen_apps/app_manager.h",
+    "lock_screen_apps/app_manager_impl.cc",
+    "lock_screen_apps/app_manager_impl.h",
     "lock_screen_apps/state_controller.cc",
     "lock_screen_apps/state_controller.h",
     "lock_screen_apps/state_observer.h",
@@ -1682,6 +1685,7 @@ source_set("unit_tests") {
     "input_method/input_method_manager_impl_unittest.cc",
     "input_method/input_method_persistence_unittest.cc",
     "locale_change_guard_unittest.cc",
+    "lock_screen_apps/app_manager_impl_unittest.cc",
     "lock_screen_apps/state_controller_unittest.cc",
     "login/auth/cryptohome_authenticator_unittest.cc",
     "login/easy_unlock/easy_unlock_challenge_wrapper_unittest.cc",