[Sync] Move sessions files from sync_driver to sync_sessions.

components/sync_driver/BUILD.gn

Index: components/sync_driver/BUILD.gn
diff --git a/components/sync_driver/BUILD.gn b/components/sync_driver/BUILD.gn
index 23c8cb99a53fea92956168fabcceabfeac7e009e..d4bd6dd7b7fd6d80e8249bdcfe2b6cc871ab7e39 100644
--- a/components/sync_driver/BUILD.gn
+++ b/components/sync_driver/BUILD.gn
@@ -57,9 +57,6 @@ source_set("sync_driver") {
     "glue/sync_backend_host_impl.h",
     "glue/sync_backend_registrar.cc",
     "glue/sync_backend_registrar.h",
-    "glue/synced_session.cc",
-    "glue/synced_session.h",
-    "glue/synced_window_delegate.h",
     "glue/ui_model_worker.cc",
     "glue/ui_model_worker.h",
     "invalidation_adapter.cc",
@@ -78,8 +75,6 @@ source_set("sync_driver") {
     "non_frontend_data_type_controller.h",
     "non_ui_data_type_controller.cc",
     "non_ui_data_type_controller.h",
-    "open_tabs_ui_delegate.cc",
-    "open_tabs_ui_delegate.h",
     "pref_names.cc",
     "pref_names.h",
     "profile_sync_auth_provider.cc",
@@ -88,8 +83,6 @@ source_set("sync_driver") {
     "protocol_event_observer.h",
     "proxy_data_type_controller.cc",
     "proxy_data_type_controller.h",
-    "sessions/synced_window_delegates_getter.cc",
-    "sessions/synced_window_delegates_getter.h",
     "shared_change_processor.cc",
     "shared_change_processor.h",
     "shared_change_processor_ref.cc",
@@ -122,8 +115,6 @@ source_set("sync_driver") {
     "sync_util.h",
     "system_encryptor.cc",
     "system_encryptor.h",
-    "tab_node_pool.cc",
-    "tab_node_pool.h",
     "ui_data_type_controller.cc",
     "ui_data_type_controller.h",
     "user_selectable_sync_type.h",
@@ -137,7 +128,6 @@ source_set("sync_driver") {
     "//components/invalidation/public",
     "//components/os_crypt",
     "//components/pref_registry",
-    "//components/sessions",
     "//components/signin/core/browser",
     "//components/version_info",
     "//google_apis",
@@ -203,7 +193,6 @@ source_set("test_support") {
     "//base",
     "//components/autofill/core/browser",
     "//components/password_manager/core/browser",
-    "//components/sessions",
     "//components/version_info",
     "//google_apis",
     "//sync:test_support_sync_internal_api",
@@ -236,7 +225,6 @@ source_set("unit_tests") {
     "sync_stopped_reporter_unittest.cc",
     "sync_util_unittest.cc",
     "system_encryptor_unittest.cc",
-    "tab_node_pool_unittest.cc",
     "ui_data_type_controller_unittest.cc",
   ]
   deps = [