Use %pure-parser in grammar files to make Bison 3 happy.

Source/core/css/CSSGrammar.y

 %{
 
 /*
  *  Copyright (C) 2002-2003 Lars Knoll (knoll@kde.org)
  *  Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved.
  *  Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *  Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  *  Copyright (C) 2012 Intel Corporation. All rights reserved.
  *
  *  This library is free software; you can redistribute it and/or
@@ skipping 42 matching lines @@
 #define YYLTYPE_IS_TRIVIAL 1
 #define YYMAXDEPTH 10000
 #define YYDEBUG 0
 
 #if YYDEBUG > 0
 #define YYPRINT(File,Type,Value) if (isCSSTokenAString(Type)) YYFPRINTF(File, "%s", String((Value).string).utf8().data())
 #endif
 
 %}
 
-%pure_parser
+%pure-parser
 
 %parse-param { BisonCSSParser* parser }
 %lex-param { BisonCSSParser* parser }
 
 %union {
     bool boolean;
     char character;
     int integer;
     double number;
     CSSParserString string;
@@ skipping 1778 matching lines @@
     ;
 
 rule_error_recovery:
     /* empty */
   | rule_error_recovery error
   | rule_error_recovery invalid_square_brackets_block
   | rule_error_recovery invalid_parentheses_block
     ;
 
 %%