Update build-tools to ab/3916447 am: eb2e878dfa am: f71bfb82ac am: eb4eb3ff48
am: 283e87cf6c

Change-Id: I44f7ae492b3774ce024e140b7ae7db78a6759cfa
tree: fa7607f1a6931d8c2b67cc23edb59fa05373a83d
  1. darwin-x86/
  2. linux-x86/
  3. build-prebuilts.sh
  4. manifest.xml