Make wcm not misuse the expected results.

pkgs/typed-racket-pkgs/typed-racket-lib/typed-racket/typecheck/tc-expr-unit.rkt

@@ -292,7 +292,7 @@
           ;(tc-expr/check/type #'e2 Univ)
           ;(tc-expr/check #'e3 expected)
           (tc-error/expr "with-continuation-mark requires a continuation-mark-key, but got ~a" key-t
-                         #:return expected)])]
+                         #:return (ret -Bottom))])]
       ;; application
       [(#%plain-app . _) (tc/app/check form expected)]
       ;; #%expression

pkgs/typed-racket-pkgs/typed-racket-test/tests/typed-racket/unit-tests/typecheck-tests.rkt

@@ -836,6 +836,9 @@
                   3)]
         [tc-err (with-continuation-mark 1 2 (5 4))]
 
+        [tc-err (with-continuation-mark 'x 'y 'z)
+          #:ret (ret (-val 'z))
+          #:expected (ret (-val 'z) -no-filter -no-obj)]
 
 
         ;; call-with-values