Fix python scripts in src/tools/

tools/site_compare/scrapers/firefox/firefox2.py

-#!/usr/bin/python2.4
-# Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+#!/usr/bin/env python
+# Copyright (c) 2011 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.
 
 """Does scraping for Firefox 2.0."""
 
 import pywintypes
 import time
 import types
 
 from drivers import keyboard
@@ skipping 212 matching lines @@
   if proc:
     count = 0
     while (len(windowing.FindChildWindows(0, "MozillaUIWindowClass"))
       and count < 5):
       keyboard.TypeString("[w]", True)
       time.sleep(1)
       count = count + 1
   return ret
 
 
-if __name__ == "__main__":
+def main():
   # We're being invoked rather than imported, so run some tests
   path = r"c:\sitecompare\scrapes\Firefox\2.0.0.6"
   windowing.PreparePath(path)
 
   # Scrape three sites and save the results
   Scrape(
     ["http://www.microsoft.com", "http://www.google.com",
      "http://www.sun.com"],
     path, (1024, 768), (0, 0))
+  return 0
 
+
+if __name__ == "__main__":
+  sys.exit(main())