This CL fixes the UnboundLocalError in wasm-api-tests testsuite

TBR=machenbach@chromium.org

Bug: chromium:1091200
Change-Id: I3830153b5bd04c3bbe8bedaa8ed79f79c5139a5d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2238574Reviewed-by: Tamer Tas <tmrts@chromium.org>
Auto-Submit: Tamer Tas <tmrts@chromium.org>
Commit-Queue: Tamer Tas <tmrts@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68295}