Rollup merge of #114022 - oli-obk:tait_ice_alias_field_projection, r=cjgillot

Perform OpaqueCast field projection on HIR, too.

fixes #105819

This is necessary for closure captures in 2021 edition, as they capture individual fields, not the full mentioned variables. So it may try to capture a field of an opaque (because the hidden type is known to be something with a field).

See https://github.com/rust-lang/rust/pull/99806 for when and why we added OpaqueCast to MIR.

clippy_utils/src/sugg.rs

@@ -1011,6 +1011,8 @@ impl<'tcx> Delegate<'tcx> for DerefDelegate<'_, 'tcx> {
                         },
                         // note: unable to trigger `Subslice` kind in tests
                         ProjectionKind::Subslice => (),
+                        // Doesn't have surface syntax. Only occurs in patterns.
+                        ProjectionKind::OpaqueCast => (),
                         ProjectionKind::Deref => {
                             // Explicit derefs are typically handled later on, but
                             // some items do not need explicit deref, such as array accesses,