Fix trychange.py --dry_run to do what the doc says.

trychange.py

 #!/usr/bin/python
 # Copyright (c) 2009 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.
 """Client-side script to send a try job to the try server. It communicates to
 the try server by either writting to a svn repository or by directly connecting
 to the server by HTTP.
 """
 
 import datetime
@@ skipping 310 matching lines @@
   if options.proxy:
     if options.proxy.lower() == 'none':
       # Effectively disable HTTP_PROXY or Internet settings proxy setup.
       proxies = {}
     else:
       proxies = {'http': options.proxy, 'https': options.proxy}
 
   logging.info('Sending by HTTP')
   logging.info(description)
   logging.info(url)
+  if options.dry_run:
+    print options.diff
+    return
   logging.info(options.diff)
-  if options.dry_run:
-    return
 
   try:
     connection = urllib.urlopen(url, urllib.urlencode(values), proxies=proxies)
   except IOError, e:
     logging.warning(str(e))
     if (values.get('bot') and len(e.args) > 2 and
         e.args[2] == 'got a bad status line'):
       raise NoTryServerAccess('%s is unaccessible. Bad --bot argument?' % url)
     else:
       raise NoTryServerAccess('%s is unaccessible. Reason: %s' % (url,
@@ skipping 401 matching lines @@
   except (InvalidScript, NoTryServerAccess), e:
     if swallow_exception:
       return 1
     print e
     return 1
   return 0
 
 
 if __name__ == "__main__":
   sys.exit(TryChange(None, [], False))