Why do `_as_c_str` methods for static arrays return `Result`?

[interacsion]

#746 makes _as_c_str methods that are backed by a statically sized array return Result<&CStr, FromBytesUntilNulError> instead of &CStr. I believe the spec guarantees these members are null-terminated UTF-8 strings. Shouldn't the API reflect this?

[Ralith]

No. ash structs have public fields, so we cannot make any assumptions about the values those fields have.

[MarijnS95]

This is optionally something we could solve for returnedonly structs after #919 if we prohibit (safe) construction of those structs in the API.

It does need an opt-out for layer and driver development usage though.