[USS] Store supports hosting multiple datatypes per database

sync/syncable/model_type.cc

Index: sync/syncable/model_type.cc
diff --git a/sync/syncable/model_type.cc b/sync/syncable/model_type.cc
index af2d4901f1e59710f5504aa652c8c071f57d4fee..1dba315e6f18526ba52178c2ef6daed5c9c55a89 100644
--- a/sync/syncable/model_type.cc
+++ b/sync/syncable/model_type.cc
@@ -749,4 +749,8 @@ bool TypeSupportsOrdering(ModelType model_type) {
   return model_type == BOOKMARKS;
 }
 
+const char* ModelTypeToTag(ModelType model_type) {
+  return kModelTypeInfoMap[model_type].root_tag;
+}
+
 }  // namespace syncer