WasmModuleBuilder is a class that is used to build Wasm modules in the
asm.js parser, in the fuzzer, as well as some tests. When it comes to
Wasm tables, WasmModuleBuilder currently supports only basic tables
(before the reftypes proposal) using an ad-hoc indirect-function index
vector.
This CL adds proper support for element sections and tables that use
them in the full potential of the reftypes extension. The new
functionality will only be used in the fuzzer and potentially some tests
in the future. Along this, we drop some functionality from
WasmModuleBuilder that was only used in tests and is redundant with the
new architecture.
Additionally, we remove tables other than externref and funcref from the
fuzzer (which were not supported properly or used anyway). We will
reintroduce them at a later time.

Bug: v8:11954
Change-Id: I0a4f6e7b63b6e3d9f7da03b5202fbf14d8678332
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3122162
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76597}