[Sync] Move some things from core/ to model(_impl)/.

components/sync/model/simple_metadata_change_list.h

Index: components/sync/model/simple_metadata_change_list.h
diff --git a/components/sync/core/simple_metadata_change_list.h b/components/sync/model/simple_metadata_change_list.h
similarity index 91%
rename from components/sync/core/simple_metadata_change_list.h
rename to components/sync/model/simple_metadata_change_list.h
index 4bbb0bb0c2015710d514f0cc6e48eadf7aa03faf..32b0dfc5f9a6986e2272e59d6927b814cbf36b96 100644
--- a/components/sync/core/simple_metadata_change_list.h
+++ b/components/sync/model/simple_metadata_change_list.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef COMPONENTS_SYNC_CORE_SIMPLE_METADATA_CHANGE_LIST_H_
-#define COMPONENTS_SYNC_CORE_SIMPLE_METADATA_CHANGE_LIST_H_
+#ifndef COMPONENTS_SYNC_MODEL_SIMPLE_METADATA_CHANGE_LIST_H_
+#define COMPONENTS_SYNC_MODEL_SIMPLE_METADATA_CHANGE_LIST_H_
 
 #include <map>
 #include <memory>
@@ -63,4 +63,4 @@ class SimpleMetadataChangeList : public MetadataChangeList {
 
 }  // namespace syncer
 
-#endif  // COMPONENTS_SYNC_CORE_SIMPLE_METADATA_CHANGE_LIST_H_
+#endif  // COMPONENTS_SYNC_MODEL_SIMPLE_METADATA_CHANGE_LIST_H_