Mojo: Accept IDL files that lack explicit ordinals.

mojo/public/bindings/parser/mojo_translate.py

 #!/usr/bin/env python
 # Copyright 2013 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.
 
 """Translate parse tree to Mojom IR"""
 
 
 import sys
 
@@ skipping 13 matching lines @@
                   'string': 's',
                   'handle': 'h' }
   if kind.endswith('[]'):
     return 'a:' + MapKind(kind[0:len(kind)-2])
   if kind in map_to_kind:
     return map_to_kind[kind]
   return 'x:' + kind
 
 
 def MapOrdinal(ordinal):
+  if ordinal == None:
+    return None;
   return int(ordinal[1:])  # Strip leading '@'
 
 
 def MapFields(fields):
   out = []
   for field in fields:
     if field[0] == 'FIELD':
       out.append({'name': field[2],
                   'kind': MapKind(field[1]),
                   'ordinal': MapOrdinal(field[3])})
@@ skipping 63 matching lines @@
   if len(sys.argv) < 2:
     print("usage: %s filename" % (sys.argv[0]))
     sys.exit(1)
   tree = eval(open(sys.argv[1]).read())
   result = Translate(tree)
   print(result)
 
 
 if __name__ == '__main__':
   Main()