- array_flip() retains the last duplicate, when we need the first
- Indexes are now prepared with a list of first-duplicate code points
to search before flipping
- This affected only U+3000 in GBK
- Big5 did not use array_flip(), but its list of override code points
did not include U+2561; Big5 now flips like the others
- EUC-JP had a long list of errors, but this encoding was not
previously released
- Shift_JIS' indexes are probably not correct, still