This reverts commit 79398ab0.

Reason for revert: Makes UBSan unhappy: https://ci.chromium.org/p/v8/builders/ci/V8%20Linux64%20UBSan/10186

Original change's description:
> [wasm] Further reduce the size of WasmCode
> 
> Also, save dynamic allocations (plus their memory overhead).
> This is realized by storing the relocation information, source position
> table, and protected instruction information together in one "metadata"
> byte array.
> For each of the three components, we just store their size, such that
> the accessors can return the respecitive {Vector} views as before.
> 
> This makes each WasmCode object 24 bytes smaller on 64-bit
> architectures. It also saves a few more bytes per code object because
> less padding is needed for the individual allocations, and each dynamic
> allocation comes with some constant memory overhead.
> 
> Since the protected instructions will just be stored in a byte array
> now, some APIs are refactored to just return that byte array directly
> (instead of an array of {ProtectedInstructionData}). This also
> simplifies serialization and deserialization, and will allow for
> switching to a more compact representation in the future.
> 
> Drive-by: Add some more checks to {Vector::cast} to protect against
>   undefined behaviour.
> 
> R=​ahaas@chromium.org
> 
> Bug: v8:10254
> Change-Id: I81ca847023841110e3e52cc402fcb0349325d7af
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2078545
> Reviewed-by: Andreas Haas <ahaas@chromium.org>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Commit-Queue: Clemens Backes <clemensb@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#66596}

TBR=jkummerow@chromium.org,ahaas@chromium.org,clemensb@chromium.org,tebbi@chromium.org

Change-Id: Id80aa82cfce8942879031032b322ee66855b5600
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:10254
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2089933Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66597}