Fix non-trivial warnings hidden by -isystem

These warnings were hidden by -isystem.

Bug: 31751828
Test: m -j checkbuild
Change-Id: Ibb1aa07a6827fcbd29fc15291fcd90280c0f608d
Merged-In: Ibb1aa07a6827fcbd29fc15291fcd90280c0f608d
(cherry picked from commit 6f51c153ea5e4187a313e47ac8bad9a1a999d4e1)
12 files changed