When `derive`ing, account for HRTB on `BareFn` fields
When given
```rust
trait SomeTrait {
type SomeType<'a>;
}
#[derive(Clone)]
struct Foo<T: SomeTrait> {
x: for<'a> fn(T::SomeType<'a>)
}
```
expand to
```rust
impl<T: ::core::clone::Clone + SomeTrait> ::core::clone::Clone for Foo<T>
where for<'a> T::SomeType<'a>: ::core::clone::Clone {
#[inline]
fn clone(&self) -> Foo<T> {
Foo { x: ::core::clone::Clone::clone(&self.x) }
}
}
```
instead of the previous invalid
```
impl<T: ::core::clone::Clone + SomeTrait> ::core::clone::Clone for Foo<T>
where T::SomeType<'a>: ::core::clone::Clone {
#[inline]
fn clone(&self) -> Foo<T> {
Foo { x: ::core::clone::Clone::clone(&self.x) }
}
}
```
Fix#122622.
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