IDL parser: override Attribute production from base IDL parser

Source/bindings/scripts/blink_idl_parser.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 236 matching lines @@
                            | ExceptionField
                            | Attribute
                            | ExceptionOperation"""
         # Standard is (no Attribute, no ExceptionOperation):
         # ExceptionMember : Const
         #                 | ExceptionField
         # FIXME: In DOMException.idl, Attributes should be changed to
         # ExceptionFields, and Attribute removed from this rule.
         p[0] = p[1]
 
-    # [b47.1]
+    # [b47.1] FIXME: rename to ExceptionAttribute
+    def p_Attribute(self, p):
+        """Attribute : ReadOnly ATTRIBUTE Type identifier ';'"""
+        p[0] = self.BuildNamed('Attribute', p, 4,
+                               ListFromConcat(p[1], p[3]))
+
+    # [b47.2]
     def p_ExceptionOperation(self, p):
         """ExceptionOperation : Type identifier '(' ')' ';'"""
         # Needed to handle one case in DOMException.idl:
         # // Override in a Mozilla compatible format
         # [NotEnumerable] DOMString toString();
         # Limited form of Operation to prevent others from being added.
         # FIXME: Should be a stringifier instead.
         p[0] = self.BuildNamed('ExceptionOperation', p, 2, p[1])
 
     # Extended attributes
@@ skipping 167 matching lines @@
         return 1
     blink_idl_lexer.main(argv)
     # Important: rewrite_tables=True causes the cache file to be deleted if it
     # exists, thus making sure that PLY doesn't load it instead of regenerating
     # the parse table.
     parser = BlinkIDLParser(outputdir=outputdir, rewrite_tables=True)
 
 
 if __name__ == '__main__':
     sys.exit(main(sys.argv))