Implementation of CSS3 nav-up/down/left/right properties from CSS3 UI.

Source/core/css/CSSGrammar.y

Index: Source/core/css/CSSGrammar.y
diff --git a/Source/core/css/CSSGrammar.y b/Source/core/css/CSSGrammar.y
index 019aead2ed41b7a06014cc68153486537c20af38..407918155df1cf493dd925ba2aa170561574d26b 100644
--- a/Source/core/css/CSSGrammar.y
+++ b/Source/core/css/CSSGrammar.y
@@ -6,6 +6,7 @@
  *  Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *  Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  *  Copyright (C) 2012 Intel Corporation. All rights reserved.
+ *  Copyright (C) 2013 Opera Software ASA. All rights reserved.
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public
@@ -1607,6 +1608,7 @@ term:
   | URI maybe_space { $$.id = CSSValueInvalid; $$.string = $1; $$.unit = CSSPrimitiveValue::CSS_URI; }
   | UNICODERANGE maybe_space { $$.id = CSSValueInvalid; $$.string = $1; $$.unit = CSSPrimitiveValue::CSS_UNICODE_RANGE; }
   | HEX maybe_space { $$.id = CSSValueInvalid; $$.string = $1; $$.unit = CSSPrimitiveValue::CSS_PARSER_HEXCOLOR; }
+  | IDSEL maybe_space { $$.id = CSSValueInvalid; $$.string = $1; $$.unit = CSSPrimitiveValue::CSS_STRING; }
   | '#' maybe_space { $$.id = CSSValueInvalid; $$.string = CSSParserString(); $$.unit = CSSPrimitiveValue::CSS_PARSER_HEXCOLOR; } /* Handle error case: "color: #;" */
   /* FIXME: according to the specs a function can have a unary_operator in front. I know no case where this makes sense */
   | function maybe_space