https://cros-goldeneye.corp.google.com/chromeos/healthmonitoring/buildDetails?buildbucketId=8926507202204402960
https://cros-goldeneye.corp.google.com/chromeos/healthmonitoring/buildDetails?buildbucketId=8926507220504341776
https://cros-goldeneye.corp.google.com/chromeos/healthmonitoring/buildDetails?buildbucketId=8926507287872905728

sarien/coral/octopus builders are failing when installing chromeos-config because it cannot find ec_config.[hc]

There are other build failures happening on all builders related to a portage update (and separately fontconfig issues) so it seems possible that this could be related to the portage update.

As far as I can tell the ec_config changes landed on Dec 3rd so they should not have just started failing now.

chromeos-config-0.0.1-r29: >>> Compiling source in /build/sarien/tmp/portage/chromeos-base/chromeos-config-0.0.1-r29/work ...
chromeos-config-0.0.1-r29:  * Emitting empty c interface config for mosys.
chromeos-config-0.0.1-r29: >>> Source compiled.
chromeos-config-0.0.1-r29: >>> Test phase [not enabled]: chromeos-base/chromeos-config-0.0.1-r29
chromeos-config-0.0.1-r29:  * Running stacked hooks for pre_src_install
chromeos-config-0.0.1-r29:  *    tidy_setup ...
chromeos-config-0.0.1-r29:  [ ok ]
chromeos-config-0.0.1-r29: 
chromeos-config-0.0.1-r29: >>> Install chromeos-config-0.0.1-r29 into /build/sarien/tmp/portage/chromeos-base/chromeos-config-0.0.1-r29/image/ category chromeos-base
chromeos-config-0.0.1-r29: Traceback (most recent call last):
chromeos-config-0.0.1-r29:   File "/usr/lib/portage/python2.7/doins.py", line 611, in <module>
chromeos-config-0.0.1-r29:     sys.exit(main(sys.argv[1:]))
chromeos-config-0.0.1-r29:   File "/usr/lib/portage/python2.7/doins.py", line 602, in main
chromeos-config-0.0.1-r29:     os.path.dirname(source)):
chromeos-config-0.0.1-r29:   File "/usr/lib/portage/python2.7/doins.py", line 450, in _doins
chromeos-config-0.0.1-r29:     return install_runner.install_file(source, os.path.dirname(dest))
chromeos-config-0.0.1-r29:   File "/usr/lib/portage/python2.7/doins.py", line 386, in install_file
chromeos-config-0.0.1-r29:     return self._ins_runner.run(source, dest_dir)
chromeos-config-0.0.1-r29:   File "/usr/lib/portage/python2.7/doins.py", line 195, in run
chromeos-config-0.0.1-r29:     sstat = os.stat(source)
chromeos-config-0.0.1-r29: OSError: [Errno 2] No such file or directory: 'ec_config.c'
chromeos-config-0.0.1-r29:  * ERROR: chromeos-base/chromeos-config-0.0.1-r29::chromiumos failed (install phase):
chromeos-config-0.0.1-r29:  *   doins failed