mut self is expended as _self

[zhuhaow]

#[async_trait]
pub trait T {
    async fn f(self);
}

struct S {}

#[async_trait]
impl T for S {
    async fn f(mut self) {
        (&mut self).do_something();
    }
}

would give error

                                  ---- help: consider changing this to be mutable: `mut _self`
    (&mut self)
       ^^^^^^^^^^^ cannot borrow as mutable

[dtolnay]

Thanks! Fixed in 0.1.10.