On Windows with MSVC, compilation fails because it cannot find
the GetIsolateForPtrCompr identifier.

Change-Id: Ib03f5c5ef34e409242bbbe93ec83b7734012feb2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1878712Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64551}