Fix trivial warnings hidden by -isystem

Fix the trivial warnings that are hidden by the use of -isystem to
include frameworks/av and caught by -Werror.

Test: m -j checkbuild
Bug: 31751828
Change-Id: I155f9f772ce0a84b364313814cb7cf528b9de4eb
Merged-In: I155f9f772ce0a84b364313814cb7cf528b9de4eb
(cherry picked from commit b8c35f94470d1518e2def0582aaec4e038c92af0)
19 files changed