differ from 'default_is_root'. Ordinarily 'default_is_root' should be
false, because ordinarily a table would be not be part of the root set
if its "isRoot" member is omitted. However, garbage collection was not
differ from 'default_is_root'. Ordinarily 'default_is_root' should be
false, because ordinarily a table would be not be part of the root set
if its "isRoot" member is omitted. However, garbage collection was not