For determining OWNERS, drop reviewers specified via '-r' that aren't in email address format.

presubmit_canned_checks.py

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Generic presubmit checks that can be reused by other presubmit checks."""
 
 import os as _os
 _HERE = _os.path.dirname(_os.path.abspath(__file__))
 
 
@@ skipping 841 matching lines @@
         issue=int(issue), messages=messages)
 
 
 def _ReviewersFromChange(change):
   """Return the reviewers specified in the |change|, if any."""
   reviewers = set()
   if change.R:
     reviewers.update(set([r.strip() for r in change.R.split(',')]))
   if change.TBR:
     reviewers.update(set([r.strip() for r in change.TBR.split(',')]))
-  return reviewers
+
+  # Drop reviewers that aren't specified in email address format.
+  return set(reviewer for reviewer in reviewers if '@' in reviewer)
 
 
 def _RietveldOwnerAndReviewers(input_api, email_regexp, approval_needed=False):
   """Return the owner and reviewers of a change, if any.
 
   If approval_needed is True, only reviewers who have approved the change
   will be returned.
   """
   issue_props = _GetRietveldIssueProps(input_api, True)
   if not issue_props:
@@ skipping 186 matching lines @@
 def CheckPatchFormatted(input_api, output_api):
   import git_cl
   cmd = ['cl', 'format', '--dry-run', input_api.PresubmitLocalPath()]
   code, _ = git_cl.RunGitWithCode(cmd, suppress_stderr=True)
   if code == 2:
     return [output_api.PresubmitPromptWarning(
       'Your patch is not formatted, please run git cl format.')]
   # As this is just a warning, ignore all other errors if the user
   # happens to have a broken clang-format, doesn't use git, etc etc.
   return []