Revert "Auto merge of #92007 - oli-obk:lazy_tait2, r=nikomatsakis"

This reverts commit e7cc3bddbe, reversing
changes made to 734368a200.

compiler/rustc_middle/src/infer/canonical.rs

@@ -178,12 +178,6 @@ pub struct QueryResponse<'tcx, R> {
     pub var_values: CanonicalVarValues<'tcx>,
     pub region_constraints: QueryRegionConstraints<'tcx>,
     pub certainty: Certainty,
-    /// List of opaque types which we tried to compare to another type.
-    /// Inside the query we don't know yet whether the opaque type actually
-    /// should get its hidden type inferred. So we bubble the opaque type
-    /// and the type it was compared against upwards and let the query caller
-    /// handle it.
-    pub opaque_types: Vec<(Ty<'tcx>, Ty<'tcx>)>,
     pub value: R,
 }