Remove ParseSess methods that duplicate DiagCtxt methods.

Also add missing `#[track_caller]` attributes to `DiagCtxt` methods as
necessary to keep tests working.

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/named_anon_conflict.rs

@@ -88,6 +88,6 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
             },
             None => ExplicitLifetimeRequired::WithParamType { span, named, new_ty_span, new_ty },
         };
-        Some(self.tcx().sess.parse_sess.create_err(err))
+        Some(self.tcx().sess.dcx().create_err(err))
     }
 }