Fix a couple resolve bugs from binder refactor

[jackh726]

Fixes #83753
Fixes #83907

[rust-highfive]

r? @lcnr

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[lcnr]

this looks good to me

gj and congrats on merging the binder refactor pr ❤️ incredible work

@bors r+

[bors]

📌 Commit 3ae5fed has been approved by lcnr

[lcnr]

while we're here, the comment for that function:

rust/compiler/rustc_resolve/src/late/lifetimes.rs

Line 2641 in 3ae5fed

/// the starting trait `Bar`, we would return `Some(['b, 'a])`.

why does that return Some(['b, 'a]) instead of Some(['a, 'b])?
There are also 2 trait Bar, which is kind of weird 😅

[jackh726]

while we're here, the comment for that function:

rust/compiler/rustc_resolve/src/late/lifetimes.rs

Line 2641 in 3ae5fed

/// the starting trait `Bar`, we would return `Some(['b, 'a])`.

why does that return Some(['b, 'a]) instead of Some(['a, 'b])?
There are also 2 trait Bar, which is kind of weird 😅

Oops, the second Bar should be the only one. I'll fix that in another PR. Its ['b, 'a] because supertrait hrtbs get appended to the bound vars, so we don't have to shift existing lifetimes.