This reverts commit fb4d5480.

Reason for revert: Breaks the noembed build

Original change's description:
> Reland "[roheap] Enable shared ro-heap by default if ptr compression is disabled"
> 
> This is a reland of 81abe8f7
> 
> It also disables ro-heap sharing in nosnap builds
> 
> Original change's description:
> > [roheap] Enable shared ro-heap by default if ptr compression is disabled
> >
> > Shared read-only heap is currently incompatible with pointer compression.
> > Enable sharing only if pointer compression is disabled.
> >
> > Bug: v8:7464
> > Change-Id: I0866ac288a34eb92fc227e8beba57f4d72a69ef0
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1635509
> > Reviewed-by: Dan Elphick <delphick@chromium.org>
> > Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> > Commit-Queue: Maciej Goszczycki <goszczycki@google.com>
> > Cr-Commit-Position: refs/heads/master@{#61963}
> 
> Bug: v8:7464
> Change-Id: I6b620152d380864db2a725c25f3c916d695d4f81
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1639298
> Commit-Queue: Maciej Goszczycki <goszczycki@google.com>
> Reviewed-by: Dan Elphick <delphick@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#62015}

TBR=rmcilroy@chromium.org,delphick@chromium.org,goszczycki@google.com

Change-Id: If0ceb39a1399e3f731dfca36e6632f327c8226ec
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7464
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1648154Reviewed-by: Dan Elphick <delphick@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62051}