This CQ run failed in PublishUprevChanges:
    https://uberchromegw.corp.google.com/i/chromeos/builders/master-paladin/builds/17469

The relevant log is here:
    https://logs.chromium.org/v/?s=chromeos%2Fbb%2Fchromeos%2Fmaster-paladin%2F17469%2F%2B%2Frecipes%2Fsteps%2FPublishUprevChanges%2F0%2Fstdout

This appears to be the relevant error:
cros_mark_as_stable: Unhandled exception:
Traceback (most recent call last):
  File "/b/c/cbuild/repository/chromite/bin/cros_mark_as_stable", line 169, in <module>
    DoMain()
  File "/b/c/cbuild/repository/chromite/bin/cros_mark_as_stable", line 165, in DoMain
    commandline.ScriptWrapperMain(FindTarget)
  File "/b/c/cbuild/repository/chromite/lib/commandline.py", line 911, in ScriptWrapperMain
    ret = target(argv[1:])
  File "/b/c/cbuild/repository/chromite/scripts/cros_mark_as_stable.py", line 292, in main
    staging_branch=options.staging_branch)
  File "/b/c/cbuild/repository/chromite/scripts/cros_mark_as_stable.py", line 127, in PushChange
    git.SyncPushBranch(cwd, remote_ref.remote, remote_ref.ref)
  File "/b/c/cbuild/repository/chromite/lib/git.py", line 1306, in SyncPushBranch
    RunGit(git_repo, [subcommand, target], **kwargs)
  File "/b/c/cbuild/repository/chromite/lib/git.py", line 819, in RunGit
    ['git'] + cmd, **kwargs)
  File "/b/c/cbuild/repository/chromite/lib/retry_util.py", line 244, in GenericRetry
    return _run()
  File "/b/c/cbuild/repository/chromite/lib/retry_util.py", line 177, in _Wrapper
    ret = func(*args, **kwargs)
  File "/b/c/cbuild/repository/chromite/lib/retry_util.py", line 243, in _run
    return functor(*args, **kwargs)
  File "/b/c/cbuild/repository/chromite/lib/cros_build_lib.py", line 654, in RunCommand
    raise RunCommandError(msg, cmd_result)
chromite.lib.cros_build_lib.RunCommandError: return code: 128; command: git rebase refs/remotes/cros/master
error: Could not open overlay-scarlet/media-libs/arc-camera3-hal-rockchip-isp1/arc-camera3-hal-rockchip-isp1-0.0.1-r3.ebuild: No such file or directory
error: Failed to merge in the changes.
First, rewinding head to replay your work on top of it...
Applying: Marking 9999 ebuild for media-libs/arc-camera3-hal-rockchip-isp1 as stable.
Using index info to reconstruct a base tree...
A	overlay-scarlet/media-libs/arc-camera3-hal-rockchip-isp1/arc-camera3-hal-rockchip-isp1-0.0.1-r2.ebuild
Falling back to patching base and 3-way merge...
CONFLICT (rename/rename): Rename "overlay-scarlet/media-libs/arc-camera3-hal-rockchip-isp1/arc-camera3-hal-rockchip-isp1-0.0.1-r2.ebuild"->"overlay-rainier/media-libs/arc-camera3-hal-rockchip-isp1/arc-camera3-hal-rockchip-isp1-0.0.1-r2.ebuild" in branch "HEAD" rename "overlay-scarlet/media-libs/arc-camera3-hal-rockchip-isp1/arc-camera3-hal-rockchip-isp1-0.0.1-r2.ebuild"->"overlay-scarlet/media-libs/arc-camera3-hal-rockchip-isp1/arc-camera3-hal-rockchip-isp1-0.0.1-r3.ebuild" in "Marking 9999 ebuild for media-libs/arc-camera3-hal-rockchip-isp1 as stable."
Patch failed at 0001 Marking 9999 ebuild for media-libs/arc-camera3-hal-rockchip-isp1 as stable.
The copy of the patch that failed is found in: .git/rebase-apply/patch
Resolve all conflicts manually, mark them as resolved with
"git add/rm <conflicted_files>", then run "git rebase --continue".
You can instead skip this commit: run "git rebase --skip".
To abort and get back to the state before "git rebase", run "git rebase --abort".
cmd=['git', 'rebase', u'refs/remotes/cros/master'], cwd=/b/c/cbuild/repository/src/overlays/overlay-meowth
05:57:58: ERROR: 
return code: 1; command: /b/c/cbuild/repository/chromite/bin/cros_mark_as_stable ... Full text is too long for this bug ... ][0m
05:57:58: ERROR: /b/c/cbuild/repository/chromite/bin/cros_mark_as_stable failed (code=1)

The error is rather inscrutable: It's complaining about this
ebuild:
    overlay-scarlet/media-libs/arc-camera3-hal-rockchip-isp1/arc-camera3-hal-rockchip-isp1-0.0.1-r3.ebuild

AFAICT, that ebuild isn't affected by any of the CLs in the run.