Function shape edge being removed too early for call with nested refs

[zgrannan]

For the following Rust code:

fn maybe_switch<'a, 'b>(c: bool, x: &'a mut &'b mut String, y: &'a mut &'b mut String) {
  if c {
    std::mem::swap(x, y)
  }
}

fn main(){
   let mut rx = &mut String::from("boom"); 
   let mut ry = &mut String::from("baz");
   maybe_switch(true, &mut rx, &mut ry, );
   println!("{rx} {ry}")
}

At the end of bb3[0], the edges to the lifetime projections of ry are incorrect. The edges for the function shape itself (at the beginning of bb3[0] appear to be created correctly).