Update build-tools to ab/3725807 am: f08dad472e
am: ef321317dd

Change-Id: I33950e4e5ddf16f00e9beeefa689d03b05b40e3a
tree: 84a2f2d8702f4f48c066dd35ac09720109add26a
  1. darwin-x86/
  2. linux-x86/
  3. build-prebuilts.sh
  4. manifest.xml