This ensures the lifetime of reference values on the simulated operand
stack of the interpreter is coupled to a lifetime of the {ThreadImpl}.
We no longer directly store reference values on the stack, but maintain
a separate "reference stack" on the GC'ed heap. This will ensure the GC
traces such references properly.

The new {StackValue} safety wrapper makes sure all use-sites that access
the operand stack properly convert to/from handles when dealing with
reference values.

R=clemensh@chromium.org
TEST=mjsunit/wasm/exceptions-interpreter
BUG=v8:8091,v8:7581

Change-Id: I8c05f2d945a6def943b89be0cfca538a73df8855
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1552791
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60650}