What command line did you execute?
git cl land

What was the output?
totallyradical sdk(residential-puce-alley)> git cl land                                                                                                                                                                                     
Using 50% similarity for rename/copy detection. Override with --similarity.

It seems this repository has a Commit Queue, which can test and land changes for you. Are you sure you wish to bypass it?
Press Enter to continue, Ctrl+C to abort.
Traceback (most recent call last):
  File "/usr/local/google/home/xusydoc/build/depot_tools/git_cl.py", line 5224, in <module>
    sys.exit(main(sys.argv[1:]))
  File "/usr/local/google/home/xusydoc/build/depot_tools/git_cl.py", line 5206, in main
    return dispatcher.execute(OptionParser(), argv)
  File "/usr/local/google/home/xusydoc/build/depot_tools/subcommand.py", line 252, in execute
    return command(parser, args[1:])
  File "/usr/local/google/home/xusydoc/build/depot_tools/git_cl.py", line 4367, in CMDland
    return SendUpstream(parser, args, 'land')
  File "/usr/local/google/home/xusydoc/build/depot_tools/git_cl.py", line 3975, in SendUpstream
    options.verbose)
  File "/usr/local/google/home/xusydoc/build/depot_tools/git_cl.py", line 2310, in CMDLand
    last_upload = RunGit(['config', self._GitBranchSetting('gerritsquashhash')],
  File "/usr/local/google/home/xusydoc/build/depot_tools/git_cl.py", line 1535, in __getattr__
    return getattr(self._changelist, attr)
  File "/usr/local/google/home/xusydoc/build/depot_tools/git_cl.py", line 1523, in __getattr__
    return self._codereview_impl.__getattribute__(attr)
AttributeError: '_GerritChangelistImpl' object has no attribute '_GitBranchSetting'


What did you expect instead?
"hooray, your change landed"

It appears https://codereview.chromium.org/2259043002 is the culprit; if I check out the revision right before it things work okay (but I'm blocked on an acl issue).