34f1275880
Fix issue 85435 by restricting Fake Read precision This PR fixes the root bug of issue #85435 by restricting Fake Read precision in closures and removing the feature gate introduced in PR #85564. More info [here](https://github.com/rust-lang/rust/issues/85561#issuecomment-846223784) and [here](https://github.com/rust-lang/rust/issues/85561#issuecomment-847270533). Closes #85561 r? ``@nikomatsakis``
For high-level intro to how type checking works in rustc, see the type checking chapter of the rustc dev guide.