Revert "Recover from errors in ancillary chunks"

This reverts commit 34005e3d3d373c0c36898cc55eae48a79c8238a1.

Although I agreed with Lucas Chollet initially, I finally understood
the objection brought forth by John Bowler: "[...] it's not an
ancillary chunk type if it's not a chunk type in the first place."

I feel that more deliberation is needed on what a robust PNG decoder
should do when it stumbles upon a chunk type that fails to meet its
basic requirements. A clarifying recommendation for decoders may or
may not need to be stipulated in the PNG specification as well.

Signed-off-by: Cosmin Truta <ctruta@gmail.com>
1 file changed