First past at removing writing mode.

sky/engine/core/css/parser/BisonCSSParser-in.cpp

 /*
  * Copyright (C) 2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Nicholas Shanks <webkit@nickshanks.com>
  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2012 Adobe Systems Incorporated. All rights reserved.
  * Copyright (C) 2012 Intel Corporation. All rights reserved.
  *
@@ skipping 492 matching lines @@
         return valueID == CSSValueOver || valueID == CSSValueUnder;
     case CSSPropertyTransformStyle:
     case CSSPropertyWebkitTransformStyle:
         return valueID == CSSValueFlat || valueID == CSSValuePreserve3d;
     case CSSPropertyWebkitUserDrag: // auto | none | element
         return valueID == CSSValueAuto || valueID == CSSValueNone || valueID == CSSValueElement;
     case CSSPropertyWebkitUserModify: // read-only | read-write
         return valueID == CSSValueReadOnly || valueID == CSSValueReadWrite || valueID == CSSValueReadWritePlaintextOnly;
     case CSSPropertyWebkitUserSelect: // auto | none | text | all
         return valueID == CSSValueAuto || valueID == CSSValueNone || valueID == CSSValueText || valueID == CSSValueAll;
-    case CSSPropertyWebkitWritingMode:
-        return valueID >= CSSValueHorizontalTb && valueID <= CSSValueHorizontalBt;
     case CSSPropertyWhiteSpace: // normal | pre | nowrap
         return valueID == CSSValueNormal || valueID == CSSValuePre || valueID == CSSValuePreWrap || valueID == CSSValuePreLine || valueID == CSSValueNowrap;
     case CSSPropertyWordBreak: // normal | break-all | break-word (this is a custom extension)
         return valueID == CSSValueNormal || valueID == CSSValueBreakAll || valueID == CSSValueBreakWord;
     default:
         ASSERT_NOT_REACHED();
         return false;
     }
     return false;
 }
@@ skipping 65 matching lines @@
     case CSSPropertyWebkitMarginTopCollapse:
     case CSSPropertyWebkitPrintColorAdjust:
     case CSSPropertyWebkitRtlOrdering:
     case CSSPropertyWebkitTextCombine:
     case CSSPropertyWebkitTextEmphasisPosition:
     case CSSPropertyTransformStyle:
     case CSSPropertyWebkitTransformStyle:
     case CSSPropertyWebkitUserDrag:
     case CSSPropertyWebkitUserModify:
     case CSSPropertyWebkitUserSelect:
-    case CSSPropertyWebkitWritingMode:
     case CSSPropertyWhiteSpace:
     case CSSPropertyWordBreak:
     case CSSPropertyWordWrap:
         return true;
     case CSSPropertyAlignItems:
     case CSSPropertyAlignSelf:
         return !RuntimeEnabledFeatures::cssGridLayoutEnabled();
     default:
         return false;
     }
@@ skipping 1258 matching lines @@
         m_observer->endProperty(isImportantFound, isPropertyParsed, m_tokenizer.safeUserStringTokenOffset(), errorType);
 }
 
 void BisonCSSParser::startEndUnknownRule()
 {
     if (m_observer)
         m_observer->startEndUnknownRule();
 }
 
 }