Fix python scripts in src/tools/

tools/symsrc/pdb_fingerprint_from_img.py

 #!/usr/bin/env python
-
-# Copyright (c) 2008 The Chromium Authors. All rights reserved.
+# 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.
 
 """This will retrieve a PDBs "fingerprint" from it's corresponding executable
 image (.dll or .exe).  This is used when retrieving the PDB from the symbol
 server.  The .pdb (or cab compressed .pd_) is expected at a path like:
  foo.pdb/FINGERPRINT/foo.pdb
 
 We can retrieve the same information from the .PDB file itself, but this file
 format is much more difficult and undocumented.  Instead, we can look at the
 DLL's reference to the PDB, and use that to retrieve the information."""
 
 import sys
 import pefile
 
+
 __CV_INFO_PDB70_format__ = ('CV_INFO_PDB70',
   ('4s,CvSignature', '16s,Signature', 'L,Age'))
 
 __GUID_format__ = ('GUID',
   ('L,Data1', 'H,Data2', 'H,Data3', '8s,Data4'))
 
+
 def GetPDBInfoFromImg(filename):
   """Returns the PDB fingerprint and the pdb filename given an image file"""
 
   pe = pefile.PE(filename)
 
   for dbg in pe.DIRECTORY_ENTRY_DEBUG:
     if dbg.struct.Type == 2:  # IMAGE_DEBUG_TYPE_CODEVIEW
       off = dbg.struct.AddressOfRawData
       size = dbg.struct.SizeOfData
       data = pe.get_memory_mapped_image()[off:off+size]
 
       cv = pefile.Structure(__CV_INFO_PDB70_format__)
       cv.__unpack__(data)
       cv.PdbFileName = data[cv.sizeof():]
       guid = pefile.Structure(__GUID_format__)
       guid.__unpack__(cv.Signature)
       guid.Data4_0 = ''.join("%02X" % ord(x) for x in guid.Data4[0:2])
       guid.Data4_1 = ''.join("%02X" % ord(x) for x in guid.Data4[2:])
 
       return ("%08X%04X%04X%s%s%d" % (
           guid.Data1, guid.Data2, guid.Data3,
           guid.Data4_0, guid.Data4_1, cv.Age),
           cv.PdbFileName.split('\x00', 1)[0])
 
     break
 
-if __name__ == '__main__':
+
+def main():
   if len(sys.argv) != 2:
     print "usage: file.dll"
-    sys.exit(1)
+    return 1
 
-  (fingerprint, file) = GetPDBInfoFromImg(sys.argv[1])
-  print "%s %s" % (fingerprint, file)
+  (fingerprint, filename) = GetPDBInfoFromImg(sys.argv[1])
+  print "%s %s" % (fingerprint, filename)
+  return 0
+
+
+if __name__ == '__main__':
+  sys.exit(main())