Before this change, the child process inherits the namespace of the
process. After this change the child process inherits the namespace of
the calling isolate.
Related: DX-710
Change-Id: Idbc72e30f5796f8034cedae776d4572ad0b0360f
Reviewed-on: https://dart-review.googlesource.com/c/89460
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Zach Anderson <zra@google.com>