{WasmInternalFunction::external} might return a function that is not
a WasmExportedFunction, at which point the code in ProcessTypeFeedback
fails.

See crrev.com/c/3277878 for context.

Bug: v8:12436, v8:12166
Change-Id: I09ef96df3fc051586044dd9c2ce88d6aeeb34b9f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3306391Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78139}