[chrome_remote_control] Add pylint to PRESUMMIT and fix lint

tools/chrome_remote_control/chrome_remote_control/adb_commands.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.
+"""Brings in Chrome Android's android_commands module, which itself is a
+thin(ish) wrapper around adb."""
 import os
 import sys
 
-"""Brings in Chrome Android's android_commands module, which itself is a
-thin(ish) wrapper around adb."""
-
 # This is currently a thin wrapper around Chrome Android's
 # build scripts, located in chrome/build/android. This file exists mainly to
 # deal with locating the module.
 
 # Get build/android scripts into our path.
 sys.path.append(
     os.path.abspath(
         os.path.join(os.path.dirname(__file__),
                      '../../../build/android')))
 try:
-  from pylib import android_commands as real_android_commands
-  from pylib import forwarder
-  from pylib import valgrind_tools
-except:
+  from pylib import ( # pylint: disable=F0401
+    android_commands as real_android_commands)
+  from pylib import forwarder # pylint: disable=F0401
+  from pylib import valgrind_tools # pylint: disable=F0401
+except Exception:
   real_android_commands = None
 
 def IsAndroidSupported():
   return real_android_commands != None
 
 def GetAttachedDevices():
   """Returns a list of attached, online android devices.
 
   If a preferred device has been set with ANDROID_SERIAL, it will be first in
   the returned list."""
   return real_android_commands.GetAttachedDevices()
 
 class ADBCommands(object):
   """A thin wrapper around ADB"""
 
   def __init__(self, device):
     self._adb = real_android_commands.AndroidCommands(device)
 
+  def Adb(self):
+    return self._adb
+
   def Forward(self, local, remote):
-    ret = self._adb._adb.SendCommand('forward %s %s' % (local, remote))
+    ret = self._adb.Adb().SendCommand('forward %s %s' % (local, remote))
     assert ret == ''
 
   def RunShellCommand(self, command, timeout_time=20, log_result=False):
     """Send a command to the adb shell and return the result.
 
     Args:
       command: String containing the shell command to send. Must not include
                the single quotes as we use them to escape the whole command.
       timeout_time: Number of seconds to wait for command to respond before
         retrying, used by AdbInterface.SendShellCommand.
@@ skipping 57 matching lines @@
   def Pull(self, remote, local):
     return self._adb.Adb().Pull(remote, local)
 
   def FileExistsOnDevice(self, file_name):
     return self._adb.FileExistsOnDevice(file_name)
 
   def IsRootEnabled(self):
     return self._adb.IsRootEnabled()
 
 def HasForwarder(adb):
-  return adb.FileExistsOnDevice(forwarder.Forwarder._FORWARDER_PATH)
+  return adb.FileExistsOnDevice('/data/local/tmp/forwarder')
 
 def HowToInstallForwarder():
   return 'adb push out/$BUILD_TYPE/forwarder %s' % (
-    forwarder.Forwarder._FORWARDER_PATH)
+    '/data/local/tmp/forwarder')
 
 class Forwarder(object):
   def __init__(self, adb, host_port):
     assert HasForwarder(adb)
 
     port_pairs = [(0, host_port), ]
     tool = valgrind_tools.BaseTool()
 
     self._host_port = host_port
 
     # Currently, Forwarder requires that ../out/Debug/forwarder exists,
     # in case it needs to push it to the device. However, to get to here,
     # android_browser_finder has ensured that device HasForwarder, above.
     #
     # Therefore, here, we just need to instantiate the forwarder, no push
     # needed.
     #
     # To do this, we monkey patch adb.PushIfNeeded to a noop.
     #
     # TODO(nduca): Fix build.android.pylib.Forwarder to not need this.
-    real_push_if_needed = adb._adb.PushIfNeeded
+    real_push_if_needed = adb.Adb().PushIfNeeded
     def FakePush(_, device_path):
       assert adb.FileExistsOnDevice(device_path)
     try:
-      adb._adb.PushIfNeeded = FakePush
+      adb.Adb().PushIfNeeded = FakePush
       self._forwarder = forwarder.Forwarder(
-        adb._adb, port_pairs,
+        adb.Adb(), port_pairs,
         tool, 'localhost', 'unused')
     finally:
-      adb._adb.PushIfNeeded = real_push_if_needed
+      adb.Adb().PushIfNeeded = real_push_if_needed
     self._device_port = self._forwarder.DevicePortForHostPort(self._host_port)
 
   @property
   def url(self):
     assert self._forwarder
     return 'http://localhost:%i' % self._device_port
 
   def Close(self):
     if self._forwarder:
       self._forwarder.Close()
       self._forwarder = None