Unnecessary HasParamEnv bound on C for FnTypeExt

[bjorn3]

https://doc.rust-lang.org/nightly/nightly-rustc/rustc/ty/layout/trait.FnTypeExt.html

[varkor]

@bjorn3: what do you mean by "unnecessary"? None of the code requires the bound on the trait itself (though it is required in the impl), but that's also true for the other bounds, not just HasParamEnv.

[bjorn3]

I cant find anything referencing self.param_env() insidr the impl.

[varkor]

It's used transitively by the rustc_target::abi::TyLayoutMethods<'_, C> for `&ty::TyS<'_> impl.

[bjorn3]

I get it. I think FnTypeExt should always use ParamEnv::reveal_all() though, as it is used only after monomorphization.