*** NOT FOR LANDING *** Unprefix multicol behind a flag

Source/core/css/ComputedStyleCSSValueMapping.cpp

Index: Source/core/css/ComputedStyleCSSValueMapping.cpp
diff --git a/Source/core/css/ComputedStyleCSSValueMapping.cpp b/Source/core/css/ComputedStyleCSSValueMapping.cpp
index 8575bb40ebedcc50a133746ad28065abdeed6253..722bf30ef5c2e0f119b3113148fb3305fdd28452 100644
--- a/Source/core/css/ComputedStyleCSSValueMapping.cpp
+++ b/Source/core/css/ComputedStyleCSSValueMapping.cpp
@@ -405,7 +405,7 @@ static PassRefPtrWillBeRawPtr<CSSValueList> valuesForGridShorthand(const StylePr
 {
     RefPtrWillBeRawPtr<CSSValueList> list = CSSValueList::createSlashSeparated();
     for (size_t i = 0; i < shorthand.length(); ++i) {
-        RefPtrWillBeRawPtr<CSSValue> value = ComputedStyleCSSValueMapping::get(shorthand.properties()[i], style, layoutObject, styledNode, allowVisitedStyle);
+        RefPtrWillBeRawPtr<CSSValue> value = ComputedStyleCSSValueMapping::get(shorthand.properties()[i], style, layoutObject, styledNode, ComputedStyleCSSValueMapping::DoingShorthand, allowVisitedStyle);
         ASSERT(value);
         list->append(value.release());
     }
@@ -416,7 +416,7 @@ static PassRefPtrWillBeRawPtr<CSSValueList> valuesForShorthandProperty(const Sty
 {
     RefPtrWillBeRawPtr<CSSValueList> list = CSSValueList::createSpaceSeparated();
     for (size_t i = 0; i < shorthand.length(); ++i) {
-        RefPtrWillBeRawPtr<CSSValue> value = ComputedStyleCSSValueMapping::get(shorthand.properties()[i], style, layoutObject, styledNode, allowVisitedStyle);
+        RefPtrWillBeRawPtr<CSSValue> value = ComputedStyleCSSValueMapping::get(shorthand.properties()[i], style, layoutObject, styledNode, ComputedStyleCSSValueMapping::DoingShorthand, allowVisitedStyle);
         ASSERT(value);
         list->append(value);
     }
@@ -431,7 +431,7 @@ static PassRefPtrWillBeRawPtr<CSSValueList> valuesForBackgroundShorthand(const C
         RefPtrWillBeRawPtr<CSSValueList> list = CSSValueList::createSlashSeparated();
         RefPtrWillBeRawPtr<CSSValueList> beforeSlash = CSSValueList::createSpaceSeparated();
         if (!currLayer->next()) { // color only for final layer
-            RefPtrWillBeRawPtr<CSSValue> value = ComputedStyleCSSValueMapping::get(CSSPropertyBackgroundColor, style, layoutObject, styledNode, allowVisitedStyle);
+            RefPtrWillBeRawPtr<CSSValue> value = ComputedStyleCSSValueMapping::get(CSSPropertyBackgroundColor, style, layoutObject, styledNode, ComputedStyleCSSValueMapping::DoingShorthand, allowVisitedStyle);
             ASSERT(value);
             beforeSlash->append(value);
         }
@@ -1083,10 +1083,10 @@ static PassRefPtrWillBeRawPtr<CSSValueList> valuesForSidesShorthand(const StyleP
 {
     RefPtrWillBeRawPtr<CSSValueList> list = CSSValueList::createSpaceSeparated();
     // Assume the properties are in the usual order top, right, bottom, left.
-    RefPtrWillBeRawPtr<CSSValue> topValue = ComputedStyleCSSValueMapping::get(shorthand.properties()[0], style, layoutObject, styledNode, allowVisitedStyle);
-    RefPtrWillBeRawPtr<CSSValue> rightValue = ComputedStyleCSSValueMapping::get(shorthand.properties()[1], style, layoutObject, styledNode, allowVisitedStyle);
-    RefPtrWillBeRawPtr<CSSValue> bottomValue = ComputedStyleCSSValueMapping::get(shorthand.properties()[2], style, layoutObject, styledNode, allowVisitedStyle);
-    RefPtrWillBeRawPtr<CSSValue> leftValue = ComputedStyleCSSValueMapping::get(shorthand.properties()[3], style, layoutObject, styledNode, allowVisitedStyle);
+    RefPtrWillBeRawPtr<CSSValue> topValue = ComputedStyleCSSValueMapping::get(shorthand.properties()[0], style, layoutObject, styledNode, ComputedStyleCSSValueMapping::DoingShorthand, allowVisitedStyle);
+    RefPtrWillBeRawPtr<CSSValue> rightValue = ComputedStyleCSSValueMapping::get(shorthand.properties()[1], style, layoutObject, styledNode, ComputedStyleCSSValueMapping::DoingShorthand, allowVisitedStyle);
+    RefPtrWillBeRawPtr<CSSValue> bottomValue = ComputedStyleCSSValueMapping::get(shorthand.properties()[2], style, layoutObject, styledNode, ComputedStyleCSSValueMapping::DoingShorthand, allowVisitedStyle);
+    RefPtrWillBeRawPtr<CSSValue> leftValue = ComputedStyleCSSValueMapping::get(shorthand.properties()[3], style, layoutObject, styledNode, ComputedStyleCSSValueMapping::DoingShorthand, allowVisitedStyle);
 
     // All 4 properties must be specified.
     if (!topValue || !rightValue || !bottomValue || !leftValue)
@@ -1318,9 +1318,10 @@ PassRefPtrWillBeRawPtr<CSSValue> ComputedStyleCSSValueMapping::valueForFilter(co
     return list.release();
 }
 
-PassRefPtrWillBeRawPtr<CSSValue> ComputedStyleCSSValueMapping::get(CSSPropertyID propertyID, const ComputedStyle& style, const LayoutObject* layoutObject, Node* styledNode, bool allowVisitedStyle)
+PassRefPtrWillBeRawPtr<CSSValue> ComputedStyleCSSValueMapping::get(CSSPropertyID unresolvedProperty, const ComputedStyle& style, const LayoutObject* layoutObject, Node* styledNode, ShorthandState shorthandState, bool allowVisitedStyle)
 {
     const SVGComputedStyle& svgStyle = style.svgStyle();
+    CSSPropertyID propertyID = resolveCSSPropertyID(unresolvedProperty);
     propertyID = CSSProperty::resolveDirectionAwareProperty(propertyID, style.direction(), style.writingMode());
     switch (propertyID) {
     case CSSPropertyInvalid:
@@ -1491,24 +1492,36 @@ PassRefPtrWillBeRawPtr<CSSValue> ComputedStyleCSSValueMapping::get(CSSPropertyID
         return cssValuePool().createColorValue(allowVisitedStyle ? style.visitedDependentColor(CSSPropertyColor).rgb() : style.color().rgb());
     case CSSPropertyWebkitPrintColorAdjust:
         return cssValuePool().createValue(style.printColorAdjust());
-    case CSSPropertyWebkitColumnCount:
+    case CSSPropertyColumnCount:
+        if (unresolvedProperty != CSSPropertyAliasWebkitColumnCount && shorthandState != DoingShorthand && !RuntimeEnabledFeatures::unprefixMulticolEnabled())
+            return nullptr;
         if (style.hasAutoColumnCount())
             return cssValuePool().createIdentifierValue(CSSValueAuto);
         return cssValuePool().createValue(style.columnCount(), CSSPrimitiveValue::CSS_NUMBER);
     case CSSPropertyColumnFill:
-        ASSERT(RuntimeEnabledFeatures::regionBasedColumnsEnabled());
+        ASSERT(RuntimeEnabledFeatures::unprefixMulticolEnabled());
         return cssValuePool().createValue(style.columnFill());
-    case CSSPropertyWebkitColumnGap:
+    case CSSPropertyColumnGap:
+        if (unresolvedProperty != CSSPropertyAliasWebkitColumnGap && !RuntimeEnabledFeatures::unprefixMulticolEnabled())
+            return nullptr;
         if (style.hasNormalColumnGap())
             return cssValuePool().createIdentifierValue(CSSValueNormal);
         return zoomAdjustedPixelValue(style.columnGap(), style);
-    case CSSPropertyWebkitColumnRuleColor:
+    case CSSPropertyColumnRuleColor:
+        if (unresolvedProperty != CSSPropertyAliasWebkitColumnRuleColor && shorthandState != DoingShorthand && !RuntimeEnabledFeatures::unprefixMulticolEnabled())
+            return nullptr;
         return allowVisitedStyle ? cssValuePool().createColorValue(style.visitedDependentColor(CSSPropertyOutlineColor).rgb()) : currentColorOrValidColor(style, style.columnRuleColor());
-    case CSSPropertyWebkitColumnRuleStyle:
+    case CSSPropertyColumnRuleStyle:
+        if (unresolvedProperty != CSSPropertyAliasWebkitColumnRuleStyle && shorthandState != DoingShorthand && !RuntimeEnabledFeatures::unprefixMulticolEnabled())
+            return nullptr;
         return cssValuePool().createValue(style.columnRuleStyle());
-    case CSSPropertyWebkitColumnRuleWidth:
+    case CSSPropertyColumnRuleWidth:
+        if (unresolvedProperty != CSSPropertyAliasWebkitColumnRuleWidth && shorthandState != DoingShorthand && !RuntimeEnabledFeatures::unprefixMulticolEnabled())
+            return nullptr;
         return zoomAdjustedPixelValue(style.columnRuleWidth(), style);
-    case CSSPropertyWebkitColumnSpan:
+    case CSSPropertyColumnSpan:
+        if (unresolvedProperty != CSSPropertyAliasWebkitColumnSpan && !RuntimeEnabledFeatures::unprefixMulticolEnabled())
+            return nullptr;
         return cssValuePool().createIdentifierValue(style.columnSpan() ? CSSValueAll : CSSValueNone);
     case CSSPropertyWebkitColumnBreakAfter:
         return cssValuePool().createValue(style.columnBreakAfter());
@@ -1516,7 +1529,9 @@ PassRefPtrWillBeRawPtr<CSSValue> ComputedStyleCSSValueMapping::get(CSSPropertyID
         return cssValuePool().createValue(style.columnBreakBefore());
     case CSSPropertyWebkitColumnBreakInside:
         return cssValuePool().createValue(style.columnBreakInside());
-    case CSSPropertyWebkitColumnWidth:
+    case CSSPropertyColumnWidth:
+        if (unresolvedProperty != CSSPropertyAliasWebkitColumnWidth && shorthandState != DoingShorthand && !RuntimeEnabledFeatures::unprefixMulticolEnabled())
+            return nullptr;
         if (style.hasAutoColumnWidth())
             return cssValuePool().createIdentifierValue(CSSValueAuto);
         return zoomAdjustedPixelValue(style.columnWidth(), style);
@@ -2312,14 +2327,14 @@ PassRefPtrWillBeRawPtr<CSSValue> ComputedStyleCSSValueMapping::get(CSSPropertyID
     case CSSPropertyBackground:
         return valuesForBackgroundShorthand(style, layoutObject, styledNode, allowVisitedStyle);
     case CSSPropertyBorder: {
-        RefPtrWillBeRawPtr<CSSValue> value = get(CSSPropertyBorderTop, style, layoutObject, styledNode, allowVisitedStyle);
+        RefPtrWillBeRawPtr<CSSValue> value = get(CSSPropertyBorderTop, style, layoutObject, styledNode, DoingShorthand, allowVisitedStyle);
         const CSSPropertyID properties[] = {
             CSSPropertyBorderRight,
             CSSPropertyBorderBottom,
             CSSPropertyBorderLeft
         };
         for (size_t i = 0; i < WTF_ARRAY_LENGTH(properties); ++i) {
-            if (!compareCSSValuePtr<CSSValue>(value, get(properties[i], style, layoutObject, styledNode, allowVisitedStyle)))
+            if (!compareCSSValuePtr<CSSValue>(value, get(properties[i], style, layoutObject, styledNode, DoingShorthand, allowVisitedStyle)))
                 return nullptr;
         }
         return value.release();
@@ -2342,10 +2357,14 @@ PassRefPtrWillBeRawPtr<CSSValue> ComputedStyleCSSValueMapping::get(CSSPropertyID
         return valuesForShorthandProperty(borderTopShorthand(), style, layoutObject, styledNode, allowVisitedStyle);
     case CSSPropertyBorderWidth:
         return valuesForSidesShorthand(borderWidthShorthand(), style, layoutObject, styledNode, allowVisitedStyle);
-    case CSSPropertyWebkitColumnRule:
-        return valuesForShorthandProperty(webkitColumnRuleShorthand(), style, layoutObject, styledNode, allowVisitedStyle);
-    case CSSPropertyWebkitColumns:
-        return valuesForShorthandProperty(webkitColumnsShorthand(), style, layoutObject, styledNode, allowVisitedStyle);
+    case CSSPropertyColumnRule:
+        if (unresolvedProperty != CSSPropertyAliasWebkitColumnRule && !RuntimeEnabledFeatures::unprefixMulticolEnabled())
+            return nullptr;
+        return valuesForShorthandProperty(columnRuleShorthand(), style, layoutObject, styledNode, allowVisitedStyle);
+    case CSSPropertyColumns:
+        if (unresolvedProperty != CSSPropertyAliasWebkitColumns && !RuntimeEnabledFeatures::unprefixMulticolEnabled())
+            return nullptr;
+        return valuesForShorthandProperty(columnsShorthand(), style, layoutObject, styledNode, allowVisitedStyle);
     case CSSPropertyListStyle:
         return valuesForShorthandProperty(listStyleShorthand(), style, layoutObject, styledNode, allowVisitedStyle);
     case CSSPropertyMargin: