Enable presubmit pylint in build/android.

build/android/pylib/utils/reraiser_thread.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.
 
 """Thread and ThreadGroup that reraise exceptions on the main thread."""
 
 import logging
 import sys
 import threading
-import time
 import traceback
 
-import watchdog_timer
+from . import watchdog_timer
 
 
 class TimeoutError(Exception):
   """Module-specific timeout exception."""
   pass
 
 
 def LogThreadStack(thread):
   """Log the stack for the given thread.
 
   Args:
     thread: a threading.Thread instance.
   """
   stack = sys._current_frames()[thread.ident]
   logging.critical('*' * 80)
   logging.critical('Stack dump for thread \'%s\'', thread.name)
   logging.critical('*' * 80)
   for filename, lineno, name, line in traceback.extract_stack(stack):
     logging.critical('File: "%s", line %d, in %s', filename, lineno, name)
     if line:
       logging.critical('  %s', line.strip())
   logging.critical('*' * 80)
 
 
 class ReraiserThread(threading.Thread):
   """Thread class that can reraise exceptions."""
 
-  def __init__(self, func, args=[], kwargs={}, name=None):
+  def __init__(self, func, args=None, kwargs=None, name=None):
     """Initialize thread.
 
     Args:
       func: callable to call on a new thread.
       args: list of positional arguments for callable, defaults to empty.
       kwargs: dictionary of keyword arguments for callable, defaults to empty.
       name: thread name, defaults to Thread-N.
     """
     super(ReraiserThread, self).__init__(name=name)
+    if not args:
+      args = []
+    if not kwargs:
+      kwargs = {}
     self.daemon = True
     self._func = func
     self._args = args
     self._kwargs = kwargs
     self._exc_info = None
 
   def ReraiseIfException(self):
     """Reraise exception if an exception was raised in the thread."""
     if self._exc_info:
       raise self._exc_info[0], self._exc_info[1], self._exc_info[2]
 
   #override
   def run(self):
     """Overrides Thread.run() to add support for reraising exceptions."""
     try:
       self._func(*self._args, **self._kwargs)
     except:
       self._exc_info = sys.exc_info()
       raise
 
 
 class ReraiserThreadGroup(object):
   """A group of ReraiserThread objects."""
 
-  def __init__(self, threads=[]):
+  def __init__(self, threads=None):
     """Initialize thread group.
 
     Args:
       threads: a list of ReraiserThread objects; defaults to empty.
     """
+    if not threads:
+      threads = []
     self._threads = threads
 
   def Add(self, thread):
     """Add a thread to the group.
 
     Args:
       thread: a ReraiserThread object.
     """
     self._threads.append(thread)
 
@@ skipping 34 matching lines @@
 
     Args:
       watcher: Watchdog object providing timeout, by default waits forever.
     """
     try:
       self._JoinAll(watcher)
     except TimeoutError:
       for thread in (t for t in self._threads if t.isAlive()):
         LogThreadStack(thread)
       raise