This adds a new {base::OS::SetDataReadOnly} method, which is similar to
{SetPermissions(kRead)}, but using another system call on Windows such
that it works on pages in the data segment.
{VirtualAlloc} will fail if called on a page of the data section,
whereas {VirtualProtect} succeeds. For the general {SetPermissions}
API we still want to use {VirtualAlloc} though, as it also changes the "committed" state of the pages.

Note that we do not add a platform API for this, as the memory was
never allocated through the platform. We just directly protect it in
V8.

R=mlippautz@chromium.org

Bug: v8:12887
Change-Id: If83bf6e5c500cc5cf08c76d04dfac5e2b4d35a2d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3820482Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82349}