IDL: Add error handlings to avoid infinite loops

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 265 matching lines @@
   # [11]
   def p_Dictionary(self, p):
     """Dictionary : DICTIONARY identifier Inheritance '{' DictionaryMembers '}' ';'"""
     p[0] = self.BuildNamed('Dictionary', p, 2, ListFromConcat(p[3], p[5]))
 
   # [11.1] Error recovery for regular Dictionary
   def p_DictionaryError(self, p):
     """Dictionary : DICTIONARY error ';'"""
     p[0] = self.BuildError(p, 'Dictionary')
 
+  # [11.2] Error recovery for regular Dictionary
+  # (for errors inside dictionary definition)
+  def p_DictionaryError2(self, p):
+    """Dictionary : DICTIONARY identifier Inheritance '{' error"""
+    p[0] = self.BuildError(p, 'Dictionary')
+
   # [12]
   def p_DictionaryMembers(self, p):
     """DictionaryMembers : ExtendedAttributeList DictionaryMember DictionaryMembers
                          |"""
     if len(p) > 1:
       p[2].AddChildren(p[1])
       p[0] = ListFromConcat(p[2], p[3])
 
   # [13]
   def p_DictionaryMember(self, p):
@@ skipping 287 matching lines @@
     """ArgumentList : error """
     p[0] = self.BuildError(p, 'ArgumentList')
 
   # [54]
   def p_Arguments(self, p):
     """Arguments : ',' Argument Arguments
                  |"""
     if len(p) > 1:
       p[0] = ListFromConcat(p[2], p[3])
 
+  # [54.1] Arguments error recovery
+  def p_ArgumentsError(self, p):
+    """Arguments : ',' error"""
+    p[0] = self.BuildError(p, 'Arguments')
+
   # [55]
   def p_Argument(self, p):
     """Argument : ExtendedAttributeList OptionalOrRequiredArgument"""
     p[2].AddChildren(p[1])
     p[0] = p[2]
 
   # [56]
   def p_OptionalOrRequiredArgument(self, p):
     """OptionalOrRequiredArgument : OPTIONAL Type ArgumentName Default
                                   | Type Ellipsis ArgumentName"""
@@ skipping 543 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:]))