The generic wrapper can be used for Wasm functions with int32 parameters
and 0 or 1 int32 return values.

Added tests for cases when the return value can & cannot be converted to
a Smi.

Bug: v8:10701
Change-Id: I470954ed0aced0e4ec6e65a9f38caac19c576549
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2390141
Commit-Queue: Eva Herencsárová <evih@google.com>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69700}