The function used raw pointers but also created Refs, which can cause
GC. Thus the code isn't safe (this has already lead to crashes in an
older version of the code).

Drive-by: Remove unnecessary native_context field (get the native
context from the context instead).

Bug: v8:12205, v8:7790
Change-Id: I4868323f48fc411e8462b7824fde3d8715b55abc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3160520
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76834}