When running wasm tests, the interpreter previously used a static
collection of function indexes stored in WasmTable to perform
call_indirect calls internal to that module. This has the wrong behavior
if the table is changed (via WasmTableObject::Set, `table.copy`, or
`table.init`).

This CL changes the cctests to always generate an intepreter entry for
all functions, and stores those entries in the dispatch table. This
allows us to use the same execution path as for non-testing code.

The interpreter entry compiler needed to be changed to support
multi-value returns too, since a 64-bit integer return value may be
lowered to two 32-bit integer returns.

Bug: v8:9016
Change-Id: I277df21ffde5c2eee0b691fcc9bab2b1a43eeffc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1531137
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60380}