[USS] Store supports hosting multiple datatypes per database

sync/internal_api/public/base/model_type.h

Index: sync/internal_api/public/base/model_type.h
diff --git a/sync/internal_api/public/base/model_type.h b/sync/internal_api/public/base/model_type.h
index 42be7f44a0d778d7288232ef0ac0dcc97021ee6e..2ad2de14cc1f280d9371d8cf1b8ccd3f6e5ee0f9 100644
--- a/sync/internal_api/public/base/model_type.h
+++ b/sync/internal_api/public/base/model_type.h
@@ -354,6 +354,11 @@ SYNC_EXPORT bool TypeSupportsHierarchy(ModelType model_type);
 // Returns true if |model_type| supports ordering of sibling entries.
 SYNC_EXPORT bool TypeSupportsOrdering(ModelType model_type);
 
+// Returns root_tag for |model_type| in ModelTypeInfo.
+// Difference with ModelTypeToRootTag(), this just simply return toor_tag in
+// ModelTypeInfo.
+SYNC_EXPORT const char* ModelTypeToTag(ModelType model_type);
+
 }  // namespace syncer
 
 #endif  // SYNC_INTERNAL_API_PUBLIC_BASE_MODEL_TYPE_H_