Revert of [wasm] Strongly typed compiled module (patchset #7 id:120001 of https://codereview.chromium.org/2340623003/ )

Reason for revert:
Forgot to correctly clone a heap number. Reverting to fix.

Original issue's description:
> [wasm] Strongly typed compiled module
>
> First stab at strongly typing the wasm compiled module FixedArray. The goal
> is to improve maintainability of the data structures living on the JS heap.
>
> My goal is to do so just for the first level, since we plan to eventually
> avoid copying the metadata bits that are currently copied from the decoded
> structures (export/import metadata, etc).
>
> Subsequent CLs will try and consolidate internal functions working off the
> compiled module as members, and evaluate what the actual interface with the
> rest of the world of this type should be - we may be able to completely
> move it in the cc file, for instance.
>
> BUG=
>
> Committed: https://crrev.com/6e03b72d9d7c0d69a4222981687757ffb0737236
> Cr-Commit-Position: refs/heads/master@{#39890}

TBR=bradnelson@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Review-Url: https://codereview.chromium.org/2383623003
Cr-Commit-Position: refs/heads/master@{#39893}