This is a partial revert of
https://github.com/google/ExoPlayer/commit/46598a46fd3c13a9be906abd6c673b9487ba5d50
The change from reset(int) to setPosition/Limit() in this file was
incorrect, the reset(int) call is important because it ensures
`bitmapData` is large enough for the `buffer.readBytes` call on L188.
Issue: #8417
PiperOrigin-RevId: 351110038
