Enable presubmit pylint in build/android.

build/android/gyp/util/build_utils.py

 # Copyright 2013 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.
 
 import fnmatch
 import json
 import os
 import pipes
 import shlex
 import shutil
 import subprocess
 import sys
-import traceback
 
 
 def MakeDirectory(dir_path):
   try:
     os.makedirs(dir_path)
   except OSError:
     pass
 
 
 def DeleteDirectory(dir_path):
   if os.path.exists(dir_path):
     shutil.rmtree(dir_path)
 
 
 def Touch(path):
   MakeDirectory(os.path.dirname(path))
   with open(path, 'a'):
     os.utime(path, None)
 
 
-def FindInDirectory(directory, filter):
+def FindInDirectory(directory, filename_filter):
   files = []
-  for root, dirnames, filenames in os.walk(directory):
-    matched_files = fnmatch.filter(filenames, filter)
+  for root, _dirnames, filenames in os.walk(directory):
+    matched_files = fnmatch.filter(filenames, filename_filter)
     files.extend((os.path.join(root, f) for f in matched_files))
   return files
 
 
-def FindInDirectories(directories, filter):
+def FindInDirectories(directories, filename_filter):
   all_files = []
   for directory in directories:
-    all_files.extend(FindInDirectory(directory, filter))
+    all_files.extend(FindInDirectory(directory, filename_filter))
   return all_files
 
 
 def ParseGypList(gyp_string):
   # The ninja generator doesn't support $ in strings, so use ## to
   # represent $.
   # TODO(cjhopman): Remove when
   # https://code.google.com/p/gyp/issues/detail?id=327
   # is addressed.
   gyp_string = gyp_string.replace('##', '$')
   return shlex.split(gyp_string)
 
 
-def CheckOptions(options, parser, required=[]):
+def CheckOptions(options, parser, required=None):
+  if not required:
+    return
   for option_name in required:
     if not getattr(options, option_name):
       parser.error('--%s is required' % option_name.replace('_', '-'))
 
 def WriteJson(obj, path, only_if_changed=False):
   old_dump = None
   if os.path.exists(path):
     with open(path, 'r') as oldfile:
       old_dump = oldfile.read()
 
   new_dump = json.dumps(obj)
 
   if not only_if_changed or old_dump != new_dump:
     with open(path, 'w') as outfile:
       outfile.write(new_dump)
 
 def ReadJson(path):
   with open(path, 'r') as jsonfile:
     return json.load(jsonfile)
 
 
 class CalledProcessError(Exception):
   """This exception is raised when the process run by CheckOutput
   exits with a non-zero exit code."""
 
   def __init__(self, cwd, args, output):
+    super(CalledProcessError, self).__init__()
     self.cwd = cwd
     self.args = args
     self.output = output
 
   def __str__(self):
     # A user should be able to simply copy and paste the command that failed
     # into their shell.
     copyable_command = '( cd {}; {} )'.format(os.path.abspath(self.cwd),
         ' '.join(map(pipes.quote, self.args)))
     return 'Command failed: {}\n{}'.format(copyable_command, self.output)
@@ skipping 26 matching lines @@
   # For a symlink, the modified time should be the greater of the link's
   # modified time and the modified time of the target.
   return max(os.lstat(path).st_mtime, os.stat(path).st_mtime)
 
 
 def IsTimeStale(output, inputs):
   if not os.path.exists(output):
     return True
 
   output_time = GetModifiedTime(output)
-  for input in inputs:
-    if GetModifiedTime(input) > output_time:
+  for i in inputs:
+    if GetModifiedTime(i) > output_time:
       return True
   return False
 
 
 def IsDeviceReady():
   device_state = CheckOutput(['adb', 'get-state'])
   return device_state.strip() == 'device'
 
 
 def PrintWarning(message):
   print 'WARNING: ' + message
 
 
 def PrintBigWarning(message):
   print '*****     ' * 8
   PrintWarning(message)
   print '*****     ' * 8