Update from https://crrev.com/312398

tools/idl_parser/idl_parser.py

 #!/usr/bin/env python
 # Copyright (c) 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.
 
 """ Parser for PPAPI IDL """
 
 #
 # IDL Parser
 #
@@ skipping 306 matching lines @@
   # [16]
   def p_Default(self, p):
     """Default : '=' DefaultValue
                |"""
     if len(p) > 1:
       p[0] = self.BuildProduction('Default', p, 2, p[2])
 
   # [17]
   def p_DefaultValue(self, p):
     """DefaultValue : ConstValue
-                    | string"""
-    if type(p[1]) == str:
+                    | string
+                    | '[' ']'"""
+    if len(p) == 3:
+      p[0] = ListFromConcat(self.BuildAttribute('TYPE', 'sequence'),
+                            self.BuildAttribute('VALUE', '[]'))
+    elif type(p[1]) == str:
       p[0] = ListFromConcat(self.BuildAttribute('TYPE', 'DOMString'),
                             self.BuildAttribute('NAME', p[1]))
     else:
       p[0] = p[1]
 
   # [] - Not specified
   def p_Exception(self, p):
     """Exception : EXCEPTION identifier Inheritance '{' ExceptionMembers '}' ';'"""
     p[0] = self.BuildNamed('Exception', p, 2, ListFromConcat(p[3], p[5]))
 
@@ skipping 855 matching lines @@
 
   print '\n'.join(ast.Tree(accept_props=['PROD']))
   if errors:
     print '\nFound %d errors.\n' % errors
 
   return errors
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv[1:]))