Previously, optimized_symbol_parsing would enable a fast path for
symbols but it never actually registered the Symbol's ext_type (so it
was always 0x0). This resulted in the optimization not working if Symbol
is registered with a different type and could additionally cause data
corruption if some other type is registered as 0x0.
Additionally, many of these Factory fields were not copied over on dup,
meaning pooled Factories would have optimized_symbol_parsing disabled if
they don't explicitly `freeze` before calling `pool` (which would do
`dup.freeze`).
Previously, optimized_symbol_parsing would enable a fast path for symbols but it never actually registered the Symbol's ext_type (so it was always 0x0). This resulted in the optimization not working if Symbol is registered with a different type and could additionally cause data corruption if some other type is registered as 0x0.
Additionally, many of these Factory fields were not copied over on dup, meaning pooled Factories would have optimized_symbol_parsing disabled if they don't explicitly freeze before calling pool (which would do dup.freeze).