Fix import

Author: Markus Westerlind

src/librustc_infer/infer/outlives/obligations.rs

@@ -64,13 +64,13 @@ use crate::infer::outlives::verify::VerifyBoundCx;
 use crate::infer::{
     self, GenericKind, InferCtxt, RegionObligation, SubregionOrigin, UndoLog, VerifyBound,
 };
-use crate::rustc_data_structures::undo_log::UndoLogs;
 use crate::traits::ObligationCause;
 use rustc_middle::ty::outlives::Component;
 use rustc_middle::ty::subst::GenericArgKind;
 use rustc_middle::ty::{self, Region, Ty, TyCtxt, TypeFoldable};
 
 use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::undo_log::UndoLogs;
 use rustc_hir as hir;
 use smallvec::smallvec;