With the edition enabled, proc_macro_path_invoc feature causes bugs with tool_attributes feature

[nrc]

With #![feature(rust_2018_preview)] and #![feature(tool_attributes)]. correct attributes give errors, e.g.,

error[E0658]: paths of length greater than one in macro invocations are currently unstable (see issue #38356)
  --> src/sealed.rs:28:3
   |
28 | #[rustfmt::skip]
   |   ^^^^^^^^^^^^^
   |
   = help: add #![feature(proc_macro_path_invoc)] to the crate attributes to enable

enabling proc_macro_path_invoc gives

error[E0433]: failed to resolve. Use of undeclared type or module `rustfmt`
  --> src/sealed.rs:28:3
   |
28 | #[rustfmt::skip]
   |   ^^^^^^^ Use of undeclared type or module `rustfmt`

Expected behaviour: no errors and the attribute is ignored by the compiler

Reported in rust-lang/rustfmt#2815

cc @gnzlbg @rust-lang/compiler @petrochenkov

[oli-obk]

dupe of #51277