Keep os/android-os.h compiling now we have __key in <sys/ipc.h>.

When we've switched the NDK to unified headers (and perhaps the
compatibility library too) we should send a whole new cleaned up
version of this file upstream...

Bug: N/A
Test: builds
Change-Id: Icf8cbd678b05bbb66bd1a4091a338c696d749478
1 file changed