https://uberchromegw.corp.google.com/i/chromeos/builders/falco-release/builds/2946

13:52:03: INFO: RunCommand: /b/c/cbuild/repository/chromite/bin/cros_sdk 'USE=-cros-debug afdo_chrome_exp1 chrome_internal' 'PARALLEL_EMERGE_STATUS_FILE=/tmp/tmpUBUcZS' -- /mnt/host/source/chromite/bin/cros_extract_deps --board falco '--format=cpe' virtual/target-os in /b/c/cbuild/repository
13:52:15: ERROR: 
return code: 1; command: /b/c/cbuild/repository/chromite/bin/cros_sdk 'USE=-cros-debug afdo_chrome_exp1 chrome_internal' 'PARALLEL_EMERGE_STATUS_FILE=/tmp/tmpUBUcZS' -- /mnt/host/source/chromite/bin/cros_extract_deps --board falco '--format=cpe' virtual/target-os
!!! The ebuild selected to satisfy "chromeos-base/chromeos-chrome" for /build/falco/ has unmet requirements.
- chromeos-base/chromeos-chrome-64.0.3249.0_rc-r2::chromiumos USE="accessibility afdo_chrome_exp1 authpolicy autotest build_tests buildcheck chrome_debug chrome_internal chrome_remoting clang cups debug_fission evdev_gestures fonts gold highdpi libcxx (multilib) nacl opengles runhooks v4l2_codec vaapi xkbcommon -afdo_chrome_exp2 -afdo_use -app_shell -asan -chrome_debug_tests -chrome_media -component_build -goma -hardfp -internal_gles_conform -lld -mojo (-neon) -opengl -thinlto -v4lplugin -verbose -vtable_verify" ABI_X86="64" OZONE_PLATFORM="default_gbm gbm -caca -cast -default_caca -default_cast -default_egltest -default_test -egltest -test" OZONE_PLATFORM_DEFAULT="gbm -caca -cast -egltest -test"
  The following REQUIRED_USE flag constraints are unsatisfied:
    afdo_chrome_exp1? ( afdo_use )
  The above constraints are a subset of the following complete expression:
    asan? ( clang ) gold? ( !lld ) lld? ( !gold ) libcxx? ( clang ) thinlto? ( clang any-of ( gold lld ) ) afdo_use? ( clang ) afdo_chrome_exp1? ( afdo_use ) afdo_chrome_exp2? ( afdo_use ) exactly-one-of ( ozone_platform_default_gbm ozone_platform_default_cast ozone_platform_default_test ozone_platform_default_egltest ozone_platform_default_caca )
(dependency required by "virtual/chromeos-interface-1-r5::chromiumos[-chromeless_tty]" [ebuild])
(dependency required by "virtual/target-chromium-os-1-r77::chromiumos" [ebuild])
(dependency required by "virtual/target-chrome-os-1-r16::chromeos" [ebuild])
(dependency required by "virtual/target-os-1.5-r1::chromeos" [ebuild])
(dependency required by "virtual/target-os" [argument])

This is related to the new afdo_chrome_exp* use flags added to falco/peppy builders.