Disable parallel sync on cygwin since it's flaky for users.

R=dpranke@chromium.org
BUG=
TEST=


Review URL: http://codereview.chromium.org/8357005

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@106359 0039d316-1c4b-4281-b951-d872f2087c98

gclient.py

@@ -1433,7 +1433,9 @@ def GenUsage(parser, command):
 def Parser():
   """Returns the default parser."""
   parser = optparse.OptionParser(version='%prog ' + __version__)
-  parser.add_option('-j', '--jobs', default=8, type='int',
+  # cygwin has issues with parallel sync
+  jobs = 1 if sys.platform == 'cygwin' else 8
+  parser.add_option('-j', '--jobs', default=jobs, type='int',
                     help='Specify how many SCM commands can run in parallel; '
                           'default=%default')
   parser.add_option('-v', '--verbose', action='count', default=0,