This CL moves the DisallowHeapAllocation scopes closer to the
callsites that get detected as GC causes by GCMole.

Bug: v8:9992
Change-Id: I3148f088ff40cee877683f214f85d745ed685a25
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1928865Reviewed-by: Dan Elphick <delphick@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65150}