Tracking issue for `str_mut_extras` and `str_box_extras`

[clarfonthey]

cc @alexcrichton @sfackler

PRs: #41096 and #41258 respectively

Notes:

• Are the naming conventions for these methods correct?

[alexbool]

What holds stabilization of these methods right now?

[SimonSapin]

@aturon @alexcrichton FCP to stabilize?

[aturon]

@rfcbot fcp merge

Covered APIs include:

• as_bytes_mut
• from_utf8_mut
• from_utf8_unchecked_mut
• <Box<str>>::into_boxed_bytes (just calls Into::into)
• from_boxed_utf8 and from_boxed_utf8_unchecked, defined in alloc:str, exported in collections::str
• exports from_utf8_mut in collections::str (missed from previous PR)

[rfcbot]

Team member @aturon has proposed to merge this. The next step is review by the rest of the tagged teams:

• @BurntSushi
• @Kimundi
• @alexcrichton
• @aturon
• @brson
• @dtolnay
• @sfackler

No concerns currently listed.

Once these reviewers reach consensus, this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.

[dtolnay]

from_boxed_utf8 no longer exists. #41258 (comment)

@rfcbot reviewed

[rfcbot]

🔔 This is now entering its final comment period, as per the review above. 🔔