https://uberchromegw.corp.google.com/i/chromeos/builders/pre-cq-launcher/builds/10612
https://uberchromegw.corp.google.com/i/chromeos/builders/pre-cq-launcher/builds/10613

Fetching project chromiumos/third_party/rootdev
error: cannot lock ref 'refs/remotes/cros/linux/v4.4.110/chromeos-4.4-kaiser-reverted': 'refs/remotes/cros/linux/v4.4.110' exists; cannot create 'refs/remotes/cros/linux/v4.4.110/chromeos-4.4-kaiser-reverted'
From https://chromium.googlesource.com/a/chromiumos/third_party/kernel
 ! [new branch]                linux/v4.4.110/chromeos-4.4-kaiser-reverted -> cros/linux/v4.4.110/chromeos-4.4-kaiser-reverted  (unable to update local ref)
error: some local refs could not be updated; try running
 'git remote prune cros' to remove any old, conflicting branches
error: Cannot fetch chromiumos/third_party/kernel
error: Exited sync due to fetch errors
real	0m49.450s
11:07:34: WARNING: Command failed with retriable error.
return code: 1; command: repo --time sync --force-sync '--cache-dir=/b/c/git' -n
cmd=['repo', '--time', 'sync', '--force-sync', '--cache-dir=/b/c/git', '-n'], cwd=/b/c/cbuild/repository
11:07:34: ERROR: return code: 1; command: repo --time sync --force-sync '--cache-dir=/b/c/git' -n
cmd=['repo', '--time', 'sync', '--force-sync', '--cache-dir=/b/c/git', '-n'], cwd=/b/c/cbuild/repository
11:07:34: ERROR: <class 'chromite.cbuildbot.repository.SrcCheckOutException'>: return code: 1; command: repo --time sync --force-sync '--cache-dir=/b/c/git' -n
cmd=['repo', '--time', 'sync', '--force-sync', '--cache-dir=/b/c/git', '-n'], cwd=/b/c/cbuild/repository
Traceback (most recent call last):
  File "/b/c/cbuild/repository/chromite/lib/failures_lib.py", line 229, in wrapped_functor
    return functor(*args, **kwargs)
  File "/b/c/cbuild/repository/chromite/cbuildbot/stages/sync_stages.py", line 2095, in PerformStage
    builder_run=self._run)
  File "/b/c/cbuild/repository/chromite/cbuildbot/validation_pool.py", line 480, in AcquirePool
    repo.Sync()
  File "/b/c/cbuild/repository/chromite/cbuildbot/repository.py", line 684, in Sync
    raise SrcCheckOutException(err_msg)
SrcCheckOutException: return code: 1; command: repo --time sync --force-sync '--cache-dir=/b/c/git' -n
cmd=['repo', '--time', 'sync', '--force-sync', '--cache-dir=/b/c/git', '-n'], cwd=/b/c/cbuild/repository

11:07:34: INFO: Translating result <class 'chromite.cbuildbot.repository.SrcCheckOutException'>: return code: 1; command: repo --time sync --force-sync '--cache-dir=/b/c/git' -n
cmd=['repo', '--time', 'sync', '--force-sync', '--cache-dir=/b/c/git', '-n'], cwd=/b/c/cbuild/repository
Traceback (most recent call last):
  File "/b/c/cbuild/repository/chromite/lib/failures_lib.py", line 229, in wrapped_functor
    return functor(*args, **kwargs)
  File "/b/c/cbuild/repository/chromite/cbuildbot/stages/sync_stages.py", line 2095, in PerformStage
    builder_run=self._run)
  File "/b/c/cbuild/repository/chromite/cbuildbot/validation_pool.py", line 480, in AcquirePool
    repo.Sync()
  File "/b/c/cbuild/repository/chromite/cbuildbot/repository.py", line 684, in Sync
    raise SrcCheckOutException(err_msg)
SrcCheckOutException: return code: 1; command: repo --time sync --force-sync '--cache-dir=/b/c/git' -n
cmd=['repo', '--time', 'sync', '--force-sync', '--cache-dir=/b/c/git', '-n'], cwd=/b/c/cbuild/repository
 to fail.