Merge changes Id210f009,I548a499d,Ic672d1c8,I0ea37067,Ieb3649b8, ...

* changes:
  sync: rename sync/sync.h to android/sync.h
  sync: move declarations from sync/sync.h to sync.c
  sync: implement sync_file_info
  sync: refactor sync_fence_info
  sync: Add NDK sync.h and libsync
  sync: Use correct type in size calculation