Mojom: Add 'default' keyword for initializing structs to non-null value.

mojo/public/tools/bindings/pylib/mojom/parse/lexer.py

 # Copyright 2014 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.
 
 import imp
 import os.path
 import sys
 
 # Disable lint check for finding modules:
 # pylint: disable=F0401
@@ skipping 48 matching lines @@
     'HANDLE',
 
     'IMPORT',
     'MODULE',
     'STRUCT',
     'INTERFACE',
     'ENUM',
     'CONST',
     'TRUE',
     'FALSE',
+    'DEFAULT',
   )
 
   keyword_map = {}
   for keyword in keywords:
     keyword_map[keyword.lower()] = keyword
 
   ##
   ## All the tokens recognized by the lexer
   ##
   tokens = keywords + (
@@ skipping 188 matching lines @@
     return t
 
   # Ignore C and C++ style comments
   def t_COMMENT(self, t):
     r'(/\*(.|\n)*?\*/)|(//.*(\n[ \t]*//.*)*)'
     t.lexer.lineno += t.value.count("\n")
 
   def t_error(self, t):
     msg = "Illegal character %s" % repr(t.value[0])
     self._error(msg, t)