Small cleanups in unescaping code.

- Rename `unescape_raw_str_or_raw_byte_str` as
  `unescape_raw_str_or_byte_str`, which is more accurate.
- Remove the unused `Mode::in_single_quotes` method.
- Make some assertions more precise, and add a missing one to
  `unescape_char_or_byte`.
- Change all the assertions to `debug_assert!`, because this code is
  reasonably hot, and the assertions aren't required for memory safety,
  and any violations are likely to be sufficiently obvious that normal
  tests will trigger them.

0 files changed, 0 insertions, 0 deletions