Various issues with pub(crate) tuple structs containing comments

[cormacrelf]

These relate specifically to pub(crate) tuple structs. Other vis modifiers are not affected. Only occurs when there is a comment before the first unnamed field.

• ASlash's comment is deleted
• AStar gets bonus nonsense
• BStar is like AStar but on one line

pub(crate) struct ASlash(
    // hello
    i32
);
// output:
// pub(crate) struct ASlash(i32);

pub(crate) struct AStar(
    /* hello */
    i32
);
// output:
// pub(crate) struct AStar(
//     crate) struct AStar(
//     /* hello */
//     i32,
// );

pub(crate) struct BStar(/* hello */ i32);
// output:
// pub(crate) struct BStar(crate) struct BStar(/* hello */ i32);

Tested on rustfmt 1.4.37-stable (c8dfcfe0 2021-09-06)

Similar to #919, but those structs were empty, but these ones have fields.

[calebcartwright]

Thanks for the report!