Add Pylint for docs server.

chrome/common/extensions/docs/server2/PRESUBMIT.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.
 
 """Presubmit script for changes affecting extensions docs server
 
 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
 for more details about the presubmit API built into depot_tools.
 """
 
@@ skipping 67 matching lines @@
       input_api.ReadFile(cron_yaml_path), key='target')
 
   if app_yaml_version == cron_yaml_version:
     return []
   return [output_api.PresubmitError(
       'Versions of app.yaml (%s) and cron.yaml (%s) must match' % (
           app_yaml_version, cron_yaml_version))]
 
 def _RunPresubmit(input_api, output_api):
   _BuildServer(input_api)
+  # For now, print any lint errors. When these have been eliminated,
+  # move these into the warning list below.
+  # See crbug.com/434363 and crbug.com/461130.
+  lint_errors = input_api.canned_checks.RunPylint(input_api, output_api)
+  if lint_errors:
+    print(lint_errors)

[not at google - send to devlin, 2015/02/24 01:01:25]

if you don't do the ''.join thing then it'll format it as a list rather than on
every line, which will look silly.

[tfarina, 2015/02/24 01:05:35]

it was not possible to do a join in the list:
AttributeError: 'list' object has no attribute 'join'

The current output is: http://pastebin.com/Cz9xeidV

[not at google - send to devlin, 2015/02/24 01:07:30]

If I said lint_errors.join('') before, I meant ''.join(lint_errors).

+
   return (
       _WarnIfAppYamlHasntChanged(input_api, output_api) +
       _CheckYamlConsistency(input_api, output_api) +
       input_api.canned_checks.RunUnitTestsInDirectory(
           input_api, output_api, '.', whitelist=WHITELIST, blacklist=BLACKLIST)
   )
 
 def CheckChangeOnUpload(input_api, output_api):
   return _RunPresubmit(input_api, output_api)
 
 def CheckChangeOnCommit(input_api, output_api):
   return _RunPresubmit(input_api, output_api)