fix gn builds on aix
Introduces `is_aix` variable and suppress non-virtual-dtor warning.
Change-Id: Iab0ceee2309d96b1efcb09fadc710362159da752
Reviewed-on: https://chromium-review.googlesource.com/1103535
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#574143}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: a1a12ef3b343f9e75c630ed6dc8f1ea44a8a747b
e1d667ef3e