[Sync] Move ModelTypeProcessor* and rename *Impl to Shared*.

sync/BUILD.gn

Index: sync/BUILD.gn
diff --git a/sync/BUILD.gn b/sync/BUILD.gn
index 9e449bdae9b7edb6a98d3497b4e81989370f9c7a..77d0454a50dd6b2754519b854d3eb33f0ccf8d4c 100644
--- a/sync/BUILD.gn
+++ b/sync/BUILD.gn
@@ -84,10 +84,6 @@ source_set("sync_core") {
     "engine/get_updates_processor.h",
     "engine/model_type_entity.cc",
     "engine/model_type_entity.h",
-    "engine/model_type_processor.cc",
-    "engine/model_type_processor.h",
-    "engine/model_type_processor_impl.cc",
-    "engine/model_type_processor_impl.h",
     "engine/model_type_worker.cc",
     "engine/model_type_worker.h",
     "engine/net/server_connection_manager.cc",
@@ -231,6 +227,8 @@ source_set("sync_core") {
     "internal_api/public/http_post_provider_interface.h",
     "internal_api/public/internal_components_factory.h",
     "internal_api/public/internal_components_factory_impl.h",
+    "internal_api/public/model_type_processor.cc",
+    "internal_api/public/model_type_processor.h",
     "internal_api/public/network_resources.h",
     "internal_api/public/non_blocking_sync_common.cc",
     "internal_api/public/non_blocking_sync_common.h",
@@ -248,6 +246,7 @@ source_set("sync_core") {
     "internal_api/public/sessions/type_debug_info_observer.h",
     "internal_api/public/sessions/update_counters.cc",
     "internal_api/public/sessions/update_counters.h",
+    "internal_api/public/shared_model_type_processor.h",
     "internal_api/public/shutdown_reason.h",
     "internal_api/public/sync_auth_provider.h",
     "internal_api/public/sync_context.h",
@@ -274,6 +273,7 @@ source_set("sync_core") {
     "internal_api/public/write_transaction.h",
     "internal_api/read_node.cc",
     "internal_api/read_transaction.cc",
+    "internal_api/shared_model_type_processor.cc",
     "internal_api/sync_backup_manager.cc",
     "internal_api/sync_backup_manager.h",
     "internal_api/sync_context.cc",
@@ -610,7 +610,6 @@ test("sync_unit_tests") {
     "engine/entity_tracker_unittest.cc",
     "engine/get_updates_processor_unittest.cc",
     "engine/model_type_entity_unittest.cc",
-    "engine/model_type_processor_impl_unittest.cc",
     "engine/model_type_worker_unittest.cc",
     "engine/sync_scheduler_unittest.cc",
     "engine/syncer_proto_util_unittest.cc",
@@ -644,6 +643,7 @@ test("sync_unit_tests") {
     "internal_api/public/sessions/sync_session_snapshot_unittest.cc",
     "internal_api/public/util/immutable_unittest.cc",
     "internal_api/public/util/weak_handle_unittest.cc",
+    "internal_api/shared_model_type_processor_unittest.cc",
     "internal_api/sync_backup_manager_unittest.cc",
     "internal_api/sync_context_proxy_impl_unittest.cc",
     "internal_api/sync_encryption_handler_impl_unittest.cc",