[Sync] Support commit only types.

components/sync/syncable/model_type.cc

 // Copyright (c) 2012 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 "components/sync/base/model_type.h"
 
 #include <stddef.h>
 
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
@@ skipping 523 matching lines @@
 ModelTypeSet PriorityCoreTypes() {
   ModelTypeSet result = ControlTypes();
 
   // The following are non-control core types.
   result.Put(SUPERVISED_USERS);
   result.Put(SUPERVISED_USER_SETTINGS);
 
   return result;
 }
 
+ModelTypeSet CommitOnlyTypes() {
+  return ModelTypeSet(USER_EVENTS);
+}
+
 const char* ModelTypeToString(ModelType model_type) {
   // This is used in serialization routines as well as for displaying debug
   // information.  Do not attempt to change these string values unless you know
   // what you're doing.
   if (model_type >= UNSPECIFIED && model_type < MODEL_TYPE_COUNT)
     return kModelTypeInfoMap[model_type].model_type_string;
   NOTREACHED() << "No known extension for model type.";
   return "Invalid";
 }
 
@@ skipping 172 matching lines @@
 bool TypeSupportsHierarchy(ModelType model_type) {
   // TODO(stanisc): crbug/438313: Should this also include TOP_LEVEL_FOLDER?
   return model_type == BOOKMARKS;
 }
 
 bool TypeSupportsOrdering(ModelType model_type) {
   return model_type == BOOKMARKS;
 }
 
 }  // namespace syncer