JSNativeContextSpecialization lowered this operator to a regular
property store, potentially ignoring a request to set the "name"
property of a function.

This CL performs the lowering only if there's no such request.

Bug: chromium:1068494
Change-Id: Ia2eaf05af9c8402f9e6450ee519a7c36c18cd44e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2139581
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67058}