Implement 'scroll-behavior' parsing

Source/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 557 matching lines @@
         break;
     case CSSPropertyPosition: // static | relative | absolute | fixed | sticky | inherit
         if (valueID == CSSValueStatic || valueID == CSSValueRelative || valueID == CSSValueAbsolute || valueID == CSSValueFixed
             || (RuntimeEnabledFeatures::cssStickyPositionEnabled() && valueID == CSSValueSticky))
             return true;
         break;
     case CSSPropertyResize: // none | both | horizontal | vertical | auto
         if (valueID == CSSValueNone || valueID == CSSValueBoth || valueID == CSSValueHorizontal || valueID == CSSValueVertical || valueID == CSSValueAuto)
             return true;
         break;
+    case CSSPropertyScrollBehavior: // instant | smooth
+        if (valueID == CSSValueInstant || valueID == CSSValueSmooth)
+            return RuntimeEnabledFeatures::cssomSmoothScrollEnabled();
     case CSSPropertySpeak: // none | normal | spell-out | digits | literal-punctuation | no-punctuation | inherit
         if (valueID == CSSValueNone || valueID == CSSValueNormal || valueID == CSSValueSpellOut || valueID == CSSValueDigits || valueID == CSSValueLiteralPunctuation || valueID == CSSValueNoPunctuation)
             return true;
         break;
     case CSSPropertyTableLayout: // auto | fixed | inherit
         if (valueID == CSSValueAuto || valueID == CSSValueFixed)
             return true;
         break;
     case CSSPropertyTextAlignLast:
         // auto | start | end | left | right | center | justify
@@ skipping 272 matching lines @@
     case CSSPropertyOutlineStyle:
     case CSSPropertyOverflowWrap:
     case CSSPropertyOverflowX:
     case CSSPropertyOverflowY:
     case CSSPropertyPageBreakAfter:
     case CSSPropertyPageBreakBefore:
     case CSSPropertyPageBreakInside:
     case CSSPropertyPointerEvents:
     case CSSPropertyPosition:
     case CSSPropertyResize:
+    case CSSPropertyScrollBehavior:
     case CSSPropertySpeak:
     case CSSPropertyTableLayout:
     case CSSPropertyTextAlignLast:
     case CSSPropertyTextJustify:
     case CSSPropertyTextLineThroughMode:
     case CSSPropertyTextLineThroughStyle:
     case CSSPropertyTextOverflow:
     case CSSPropertyTextOverlineMode:
     case CSSPropertyTextOverlineStyle:
     case CSSPropertyTextRendering:
@@ skipping 9289 matching lines @@
 {
     // The tokenizer checks for the construct of an+b.
     // However, since the {ident} rule precedes the {nth} rule, some of those
     // tokens are identified as string literal. Furthermore we need to accept
     // "odd" and "even" which does not match to an+b.
     return equalIgnoringCase(token, "odd") || equalIgnoringCase(token, "even")
         || equalIgnoringCase(token, "n") || equalIgnoringCase(token, "-n");
 }
 
 }