Do not shallow resolve to root var while fudging Fixes https://github.com/rust-lang/rust/issues/153816 and fixes https://github.com/rust-lang/rust/issues/153849 In https://github.com/rust-lang/rust/pull/151380, I thought that whether shallow resolve to root var or not wouldn't affect the actual type inferencing, but it isn't true for the fudge, in which we discard all newly created relationships between unresolved inference variables :sweat_smile: r? lcnr