Remove 'alphabetic' value from text-underline-position

Source/core/css/CSSPrimitiveValueMappings.h

 /*
  * Copyright (C) 2007 Alexey Proskuryakov <ap@nypop.com>.
  * Copyright (C) 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2009 Jeff Schiller <codedread@gmail.com>
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
@@ skipping 2487 matching lines @@
 }
 
 template<> inline CSSPrimitiveValue::CSSPrimitiveValue(TextUnderlinePosition e)
     : CSSValue(PrimitiveClass)
 {
     m_primitiveUnitType = CSS_VALUE_ID;
     switch (e) {
     case TextUnderlinePositionAuto:
         m_value.valueID = CSSValueAuto;
         break;
-    case TextUnderlinePositionAlphabetic:
-        m_value.valueID = CSSValueAlphabetic;
-        break;
     case TextUnderlinePositionUnder:
         m_value.valueID = CSSValueUnder;
         break;
     }
 
     // FIXME: Implement support for 'under left' and 'under right' values.
 }
 
 template<> inline CSSPrimitiveValue::operator TextUnderlinePosition() const
 {
     ASSERT(isValueID());
     switch (m_value.valueID) {
     case CSSValueAuto:
         return TextUnderlinePositionAuto;
-    case CSSValueAlphabetic:
-        return TextUnderlinePositionAlphabetic;
     case CSSValueUnder:
         return TextUnderlinePositionUnder;
     default:
         break;
     }
 
     // FIXME: Implement support for 'under left' and 'under right' values.
 
     ASSERT_NOT_REACHED();
     return TextUnderlinePositionAuto;
@@ skipping 2421 matching lines @@
         break;
     }
 
     ASSERT_NOT_REACHED();
     return TouchActionDelayNone;
 }
 
 }
 
 #endif