991: Use Marker argument for item parsers r=matklad a=pcpthm
Before doing this for expressions, I found that the pattern (Marker argument) should be applied to the item parsers because visiblity and modifiers are parsed in a separate function.
Fixed some parser bugs:
- Fix pub_expr: `pub 42;` was allowed.
- Fix incorrect parsing of crate::path: incorrectly parsed as `crate` as a visibility.
Co-authored-by: pcpthm <pcpthm@gmail.com>
We allow invalid inner attributes to be parsed, e.g. inner attributes that are
not directly after the opening brace of the match block.
Instead we run validation on `MatchArmList` to allow better reporting of errors.
We need to be able to get the receiver even if there is no field name yet, and
currently "a." wouldn't get parsed as a field name at all. This seems to help.
