Make tc/funapp follow contract in error case.

Closes PR 14615.

pkgs/typed-racket-pkgs/typed-racket-lib/typed-racket/typecheck/tc-funapp.rkt

@@ -160,7 +160,7 @@
       (for/list ([fty ts])
         (tc/funapp f-stx args-stx fty args-res expected)))]
     ;; error type is a perfectly good fcn type
-    [(Error:) f-type]
+    [(Error:) (ret f-type)]
     ;; otherwise fail
     [(Poly: ns (Function: arrs))
      (tc-error/expr

pkgs/typed-racket-pkgs/typed-racket-test/tests/typed-racket/fail/pr14615.rkt

@@ -0,0 +1,6 @@
+#lang typed/racket/base
+(require racket/gui)
+(define (f)
+  (let ([fn (put-file)])
+    (when fn
+      (values fn))))