Fix a bug in Warn(), simplify code

TBR=bradnelson

Review URL: http://codereview.chromium.org/2671003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@48961 0039d316-1c4b-4281-b951-d872f2087c98

gcl.py

@@ -184,14 +184,12 @@ def GetCodeReviewSetting(key):
 
 
 def Warn(msg):
-  ErrorExit(msg, exit=False)
+  print >> sys.stderr, msg
 
 
-def ErrorExit(msg, do_exit=True):
-  """Print an error message to stderr and optionally exit."""
+def ErrorExit(msg):
   print >> sys.stderr, msg
-  if do_exit:
-    sys.exit(1)
+  sys.exit(1)
 
 
 def RunShellWithReturnCode(command, print_output=False):