Fix python scripts in src/tools/

tools/checklicenses/checklicenses.py

-#!/usr/bin/python
+#!/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.
 
 """Makes sure that all files contain proper licensing information."""
 
 
 import optparse
 import os.path
 import subprocess
@@ skipping 392 matching lines @@
     ],
     'v8/test/cctest': [  # http://crbug.com/98597
         'UNKNOWN',
     ],
     'webkit/data/ico_decoder': [
         'UNKNOWN',
     ],
 }
 
 
-def main(options, args):
+def check_licenses(options, args):
   # Figure out which directory we have to check.
   if len(args) == 0:
     # No directory to check specified, use the repository root.
     start_dir = options.base_directory
   elif len(args) == 1:
     # Directory specified. Start here. It's supposed to be relative to the
     # base directory.
     start_dir = os.path.abspath(os.path.join(options.base_directory, args[0]))
   else:
     # More than one argument, we don't handle this.
     PrintUsage()
-    sys.exit(1)
+    return 1
 
   print "Using base directory:", options.base_directory
   print "Checking:", start_dir
   print
 
   licensecheck_path = os.path.abspath(os.path.join(options.base_directory,
                                                    'third_party',
                                                    'devscripts',
                                                    'licensecheck.pl'))
 
   licensecheck = subprocess.Popen([licensecheck_path, '-r', start_dir],
                                   stdout=subprocess.PIPE,
                                   stderr=subprocess.PIPE)
   stdout, stderr = licensecheck.communicate()
   if options.verbose:
     print '----------- licensecheck stdout -----------'
     print stdout
     print '--------- end licensecheck stdout ---------'
   if licensecheck.returncode != 0 or stderr:
     print '----------- licensecheck stderr -----------'
     print stderr
     print '--------- end licensecheck stderr ---------'
     print "\nFAILED\n"
-    sys.exit(1)
+    return 1
 
   success = True
   for line in stdout.splitlines():
     filename, license = line.split(':', 1)
     filename = os.path.relpath(filename.strip(), options.base_directory)
 
     # All files in the build output directory are generated one way or another.
     # There's no need to check them.
     if filename.startswith('out/') or filename.startswith('sconsbuild/'):
       continue
@@ skipping 16 matching lines @@
           found_path_specific = True
           break
       if found_path_specific:
         continue
 
     print "'%s' has non-whitelisted license '%s'" % (filename, license)
     success = False
 
   if success:
     print "\nSUCCESS\n"
-    sys.exit(0)
+    return 0
   else:
     print "\nFAILED\n"
     print "Please read",
     print "http://www.chromium.org/developers/adding-3rd-party-libraries"
     print "for more info how to handle the failure."
     print
     print "Please respect OWNERS of checklicenses.py. Changes violating"
     print "this requirement may be reverted."
-
-    sys.exit(1)
+    return 1
 
 
-if '__main__' == __name__:
+def main():
   default_root = os.path.abspath(
       os.path.join(os.path.dirname(__file__), '..', '..'))
   option_parser = optparse.OptionParser()
   option_parser.add_option('--root', default=default_root,
                            dest='base_directory',
                            help='Specifies the repository root. This defaults '
                            'to "../.." relative to the script file, which '
                            'will normally be the repository root.')
   option_parser.add_option('-v', '--verbose', action='store_true',
                            default=False, help='Print debug logging')
   option_parser.add_option('--ignore-suppressions',
                            action='store_true',
                            default=False,
                            help='Ignore path-specific license whitelist.')
   options, args = option_parser.parse_args()
-  main(options, args)
+  return check_licenses(options, args)
+
+
+if '__main__' == __name__:
+  sys.exit(main())