am ae9aa921: Merge remote-tracking branch \'aosp/upstream\'

* commit 'ae9aa921':
  Implement plugins for bootstrap go modules
  Fix bootstrap and separate buildDir ninja cleanup
  context: Changed singletons to execute in order.
  bootstrap: Added phony rule for bootstrapManifest.
  Add new line to fatal error messages in bootstrap
  bpdoc: Cache property struct docs by full package path