This was originally proposed by yangguo@ on the original CL that
introduced this, but back then it looked easier to put the map cache
onto the global object than on the native context. However it turns out
that this is indeed quite strange and also not necessarily supported (we
got crashes from the wild indicating that the `Object::GetProperty()`
might fail on the global object). So this CL simplifies the original
design and just puts the map cache onto the native context like with do
with other context specific maps.

Fixed: chromium:1167399
Bug: chromium:1127914, chromium:1159402, chromium:1071432, chromium:1164241
Change-Id: Ie16f892dd19b55b4c49e9d4829cab3c24ae64ad3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637226
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72159}