Auto merge of #92566 - the8472:inline-tra, r=m-ou-se

Inline `__iterator_get_unchecked` for some iterator adapters.

This aligns the inline attributes of existing `__iterator_get_unchecked` with those of `next()` on adapters that have both.

It improves the performance of iterators using unchecked access when building in incremental mode (due to the larger CGU count?). It might negatively affect incremental compile times for better runtime results, but considering that the equivalent `next()` implementations also are `#[inline]` and usually are more complex this should be ok.

```
./x.py bench library/core -i --stage 0 --test-args bench_trusted_random_access

OLD: 119,172 ns/iter
NEW:  17,714 ns/iter
```

0 files changed, 0 insertions, 0 deletions