When global object has proxies we should first call hasProperty and
then call GetProperty according to spec. This cl fixes both
LoadGlobal and LoadLookupGlobal to correctly handle these cases.

Also fixes tests that didn't expect hasProperty to be called.

Change-Id: I3a45df7ae24be74dd46cf04cafbf8c2d7018b3af
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1876059
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64580}