sync: Add interfaces for per-type sync

sync/sync_core.gypi

 # Copyright 2013 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.
 
 {
   'include_dirs': [
     '..',
   ],
   'defines': [
     'SYNC_IMPLEMENTATION',
@@ skipping 17 matching lines @@
   ],
   'sources': [
     'base/sync_export.h',
     'engine/all_status.cc',
     'engine/all_status.h',
     'engine/apply_control_data_updates.cc',
     'engine/apply_control_data_updates.h',
     'engine/backoff_delay_provider.cc',
     'engine/backoff_delay_provider.h',
     'engine/commit.cc',
+    'engine/commit_contribution.cc',
+    'engine/commit_contribution.h',
+    'engine/commit_contributor.cc',
+    'engine/commit_contributor.h',
     'engine/commit.h',
     'engine/commit_processor.cc',
     'engine/commit_processor.h',
     'engine/commit_util.cc',
     'engine/commit_util.h',
     'engine/conflict_resolver.cc',
     'engine/conflict_resolver.h',
     'engine/conflict_util.cc',
     'engine/conflict_util.h',
+    'engine/directory_commit_contribution.cc',
+    'engine/directory_commit_contribution.h',
+    'engine/directory_commit_contributor.cc',
+    'engine/directory_commit_contributor.h',
+    'engine/directory_update_handler.cc',
+    'engine/directory_update_handler.h',
     'engine/download.cc',
     'engine/download.h',
     'engine/get_commit_ids.cc',
     'engine/get_commit_ids.h',
     'engine/get_updates_delegate.cc',
     'engine/get_updates_delegate.h',
     'engine/get_updates_processor.cc',
     'engine/get_updates_processor.h',
     'engine/net/server_connection_manager.cc',
     'engine/net/server_connection_manager.h',
     'engine/net/url_translator.cc',
     'engine/net/url_translator.h',
     'engine/nudge_source.cc',
     'engine/nudge_source.h',
     'engine/process_updates_util.cc',
     'engine/process_updates_util.h',
     'engine/sync_cycle_event.cc',
     'engine/sync_cycle_event.h',
-    'engine/sync_directory_commit_contribution.cc',
-    'engine/sync_directory_commit_contribution.h',
-    'engine/sync_directory_commit_contributor.cc',
-    'engine/sync_directory_commit_contributor.h',
-    'engine/sync_directory_update_handler.cc',
-    'engine/sync_directory_update_handler.h',
     'engine/sync_engine_event_listener.cc',
     'engine/sync_engine_event_listener.h',
-    'engine/sync_scheduler.cc',
-    'engine/sync_scheduler.h',
-    'engine/sync_scheduler_impl.cc',
-    'engine/sync_scheduler_impl.h',
     'engine/syncer.cc',
     'engine/syncer.h',
     'engine/syncer_proto_util.cc',
     'engine/syncer_proto_util.h',
     'engine/syncer_types.h',
     'engine/syncer_util.cc',
     'engine/syncer_util.h',
+    'engine/sync_scheduler.cc',
+    'engine/sync_scheduler.h',
+    'engine/sync_scheduler_impl.cc',
+    'engine/sync_scheduler_impl.h',
     'engine/traffic_logger.cc',
     'engine/traffic_logger.h',
     'engine/traffic_recorder.cc',
     'engine/traffic_recorder.h',
     'engine/update_applicator.cc',
     'engine/update_applicator.h',
+    'engine/update_handler.cc',
+    'engine/update_handler.h',
     'js/js_arg_list.cc',
     'js/js_arg_list.h',
     'js/js_backend.h',
     'js/js_controller.h',
     'js/js_event_details.cc',
     'js/js_event_details.h',
     'js/js_event_handler.h',
     'js/js_reply_handler.h',
     'js/sync_js_controller.cc',
     'js/sync_js_controller.h',
@@ skipping 92 matching lines @@
     'util/get_session_name_win.cc',
     'util/get_session_name_win.h',
     'util/logging.cc',
     'util/logging.h',
     'util/nigori.cc',
     'util/nigori.h',
     'util/time.cc',
     'util/time.h',
   ],
 }