For now, that flag only avoid the installation of the 'WebAssembly'
global. Follow-up CLs will remove unneeded code from the binary if the gn
arg is not set to true.

R=ecmziegler@chromium.org, machenbach@chromium.org

Bug: v8:11238, v8:11344
Change-Id: Ie95b608ed12b0476470cb552138e369f863d249b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2646833
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Emanuel Ziegler <ecmziegler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72296}