engine: bundling: inconsistant renaming for inherent impls

[W95Psp]

pub mod a {
    pub fn f() {
        super::b::f()
    }

    pub struct A;
    impl A {
        pub fn a(self) {}
    }
    fn g(x: A) {
        x.a()
    }
}
pub mod b {
    pub fn f() {
        super::a::f()
    }
}


struct B;
impl B {
    fn b(self) {}
}
fn g(x: B, y: a::A) {
    x.b();
    y.a()
}

Open this code snippet in the playground

The naming scheme for a::A::a is different from the one for B::b.
a::A::a extracts to a while B::b extracts to impl__B__b.

This is not a bug, but an inconsistency.

I think we should improve that: A::a should be named impl__A__a.