Revert "eliminate LexInfo.thaw that was almost an exact duplicate of Hash.thaw". It broke LexInfo tests by changing semantic of LexInfo.init.
Revert "eliminate LexInfo.thaw that was almost an exact duplicate of
Hash.thaw". It broke LexInfo tests by changing semantic of LexInfo.init.

git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@45850 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot