Fix warn_unused_result attribute failure

On some libcs posix_memalign is defined with warn_unused_result. Check
its return value and handle it appropriately in this test.

Change-Id: Iaa7151fe101b0dfc04192229a9a8751e1f92507f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1507037
Auto-Submit: Vlad Tsyrklevich <vtsyrklevich@chromium.org>
Reviewed-by: Vitaly Buka <vitalybuka@chromium.org>
Commit-Queue: Vlad Tsyrklevich <vtsyrklevich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#638388}
1 file changed