Initial support for experimental touch-action CSS feature

Source/core/css/CSSParser.cpp

Index: Source/core/css/CSSParser.cpp
diff --git a/Source/core/css/CSSParser.cpp b/Source/core/css/CSSParser.cpp
index 83246da05126621579ab9bff0dbbc369bd42c317..dbf22344fc384860934794677b4a43d619941201 100644
--- a/Source/core/css/CSSParser.cpp
+++ b/Source/core/css/CSSParser.cpp
@@ -209,6 +209,7 @@ CSSParserContext::CSSParserContext(CSSParserMode mode, const KURL& baseURL)
     , isCSSStickyPositionEnabled(false)
     , isCSSGridLayoutEnabled(false)
     , isCSSVariablesEnabled(false)
+    , isCSSTouchActionEnabled(false)
     , needsSiteSpecificQuirks(false)
 {
 }
@@ -222,6 +223,7 @@ CSSParserContext::CSSParserContext(Document* document, const KURL& baseURL, cons
     , isCSSStickyPositionEnabled(document->cssStickyPositionEnabled())
     , isCSSGridLayoutEnabled(document->cssGridLayoutEnabled())
     , isCSSVariablesEnabled(document->settings() ? document->settings()->cssVariablesEnabled() : false)
+    , isCSSTouchActionEnabled(RuntimeEnabledFeatures::cssTouchActionEnabled())
     , needsSiteSpecificQuirks(document->settings() ? document->settings()->needsSiteSpecificQuirks() : false)
 {
 }
@@ -236,6 +238,7 @@ bool operator==(const CSSParserContext& a, const CSSParserContext& b)
         && a.isCSSStickyPositionEnabled == b.isCSSStickyPositionEnabled
         && a.isCSSGridLayoutEnabled == b.isCSSGridLayoutEnabled
         && a.isCSSVariablesEnabled == b.isCSSVariablesEnabled
+        && a.isCSSTouchActionEnabled == b.isCSSTouchActionEnabled
         && a.needsSiteSpecificQuirks == b.needsSiteSpecificQuirks;
 }
 
@@ -708,6 +711,10 @@ static inline bool isValidKeywordPropertyAndValue(CSSPropertyID propertyId, int
         if ((valueID >= CSSValueCapitalize && valueID <= CSSValueLowercase) || valueID == CSSValueNone)
             return true;
         break;
+    case CSSPropertyTouchAction: // auto | none
+        if (parserContext.isCSSTouchActionEnabled && (valueID == CSSValueAuto || valueID == CSSValueNone))
+            return true;
+        break;
     case CSSPropertyVisibility: // visible | hidden | collapse | inherit
         if (valueID == CSSValueVisible || valueID == CSSValueHidden || valueID == CSSValueCollapse)
             return true;
@@ -970,6 +977,7 @@ static inline bool isKeywordPropertyID(CSSPropertyID propertyId)
     case CSSPropertyTextTransform:
     case CSSPropertyTextUnderlineMode:
     case CSSPropertyTextUnderlineStyle:
+    case CSSPropertyTouchAction:
     case CSSPropertyVisibility:
     case CSSPropertyWebkitAppearance:
     case CSSPropertyWebkitBackfaceVisibility:
@@ -2769,6 +2777,7 @@ bool CSSParser::parseValue(CSSPropertyID propId, bool important)
     case CSSPropertyTextTransform:
     case CSSPropertyTextUnderlineMode:
     case CSSPropertyTextUnderlineStyle:
+    case CSSPropertyTouchAction:
     case CSSPropertyVariable:
     case CSSPropertyVisibility:
     case CSSPropertyWebkitAppearance: