They are suspected to be causing Canary crashes, confirmed through
local reverts and repro attempts.

This reverts:
- "Reland "[serializer] Change deferring to use forward refs""
  commit 76d684cc.
- "Reland "[serializer] Remove new space""
  commit 81231c23.
- "[serializer] Clean-up and de-macro ReadDataCase"
  commit c06d24b9.
- "[serializer] DCHECK deserializer allocations are initialized"
  commit fbc1f32d.

Bug: chromium:1128872
Change-Id: Id2bb3b8fac526fdf9ffb033222ae08cd423f8238
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2414220Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69955}