Permits running pylint without pylintrc.

pylint.py

Index: pylint.py
diff --git a/pylint.py b/pylint.py
index f24ab1780192805d0fb9d416b251c2220159ff51..168dbec667f2d438768a450305ff5c11098ccf22 100755
--- a/pylint.py
+++ b/pylint.py
@@ -18,7 +18,11 @@ _RC_FILE = os.path.join(_HERE, 'pylintrc')
 # Run pylint. We prepend the command-line with the depot_tools rcfile. If
 # another rcfile is to be used, passing --rcfile a second time on the command-
 # line will work fine.
-command = [sys.executable, _PYLINT, '--rcfile=%s' % _RC_FILE] + sys.argv[1:]
+command = [sys.executable, _PYLINT]
+if os.path.isfile(_RC_FILE):
+  # The file can be removed to test 'normal' pylint behavior.
+  command.append('--rcfile=%s' % _RC_FILE)
+command.extend(sys.argv[1:])
 try:
   sys.exit(subprocess.call(command))
 except KeyboardInterrupt: