natString.cc (rehash): Don't bother with memset; _Jv_AllocBytes returns zero'd memory.
* java/lang/natString.cc (rehash): Don't bother with memset;
_Jv_AllocBytes returns zero'd memory. Use _Jv_AllocBytesChecked.
Use UNMASK_PTR.
(UNMASK_PTR): New macro.
(intern): Unmask pointer before returning it. Register finalizer
for the string.
(unintern): Handle case where
(MASK_PTR): New macro.
(PTR_MAKSED): Likewise.
(_Jv_NewStringUtf8Const): Use UNMASK_PTR.