Restore the nonull warning in chrome/browser/ui for everything but mac

-Wno-null has been disabled for clang in chrome/browser/ui since 2015
but it seems to be enough to disable that warning for mac (the only
platform that used clang by default in 2015).

Bug: 383820
Change-Id: Iadc03f761c120db91fb806369ecf6f3bd8459c1c
Reviewed-on: https://chromium-review.googlesource.com/c/982057
Commit-Queue: Nico Weber <thakis@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608368}
1 file changed