Fix python scripts in src/tools/

tools/site_compare/scrapers/chrome/chromebase.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 all currently-known versions of Chrome"""
 
 import pywintypes
 import types
 
 from drivers import keyboard
 from drivers import mouse
 from drivers import windowing
 
+
 # TODO: this has moved, use some logic to find it. For now,
 # expects a subst k:.
 DEFAULT_PATH = r"k:\chrome.exe"
 
+
 def InvokeBrowser(path):
   """Invoke the Chrome browser.
 
   Args:
     path: full path to browser
 
   Returns:
     A tuple of (main window, process handle, address bar, render pane)
   """
 
@@ skipping 143 matching lines @@
 
   if proc:
     windowing.SetForegroundWindow(wnd)
     keyboard.TypeString(r"{\4}", use_modifiers=True)
     if not windowing.WaitForProcessExit(proc, timeout):
       windowing.EndProcess(proc)
 
   return ret
 
 
-if __name__ == "__main__":
+def main():
   # We're being invoked rather than imported, so run some tests
   path = r"c:\sitecompare\scrapes\chrome\0.1.97.0"
   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())