CSSValue Immediates: Replace CSSPrimitiveValue usage with const references

Source/core/css/resolver/StyleBuilderConverter.cpp

Index: Source/core/css/resolver/StyleBuilderConverter.cpp
diff --git a/Source/core/css/resolver/StyleBuilderConverter.cpp b/Source/core/css/resolver/StyleBuilderConverter.cpp
index 5b3100b7772e60942fdb9a2595c383fa6009f278..337ff26b4194cccc4d4ef04c510446672bfdf831 100644
--- a/Source/core/css/resolver/StyleBuilderConverter.cpp
+++ b/Source/core/css/resolver/StyleBuilderConverter.cpp
@@ -47,7 +47,7 @@ namespace blink {
 
 namespace {
 
-static GridLength convertGridTrackBreadth(const StyleResolverState& state, CSSPrimitiveValue primitiveValue)
+static GridLength convertGridTrackBreadth(const StyleResolverState& state, const CSSPrimitiveValue& primitiveValue)
 {
     if (primitiveValue.getValueID() == CSSValueMinContent)
         return Length(MinContent);
@@ -64,7 +64,7 @@ static GridLength convertGridTrackBreadth(const StyleResolverState& state, CSSPr
 
 } // namespace
 
-PassRefPtr<StyleReflection> StyleBuilderConverter::convertBoxReflect(StyleResolverState& state, CSSValue value)
+PassRefPtr<StyleReflection> StyleBuilderConverter::convertBoxReflect(StyleResolverState& state, const CSSValue& value)
 {
     if (value.isPrimitiveValue()) {
         ASSERT(toCSSPrimitiveValue(value).getValueID() == CSSValueNone);
@@ -83,21 +83,21 @@ PassRefPtr<StyleReflection> StyleBuilderConverter::convertBoxReflect(StyleResolv
     return reflection.release();
 }
 
-Color StyleBuilderConverter::convertColor(StyleResolverState& state, CSSValue value, bool forVisitedLink)
+Color StyleBuilderConverter::convertColor(StyleResolverState& state, const CSSValue& value, bool forVisitedLink)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     return state.document().textLinkColors().colorFromPrimitiveValue(primitiveValue, state.style()->color(), forVisitedLink);
 }
 
-AtomicString StyleBuilderConverter::convertFragmentIdentifier(StyleResolverState& state, CSSValue value)
+AtomicString StyleBuilderConverter::convertFragmentIdentifier(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue.isURI())
         return SVGURIReference::fragmentIdentifierFromIRIString(primitiveValue.getStringValue(), state.element()->treeScope());
     return nullAtom;
 }
 
-LengthBox StyleBuilderConverter::convertClip(StyleResolverState& state, CSSValue value)
+LengthBox StyleBuilderConverter::convertClip(StyleResolverState& state, const CSSValue& value)
 {
     Rect* rect = toCSSPrimitiveValue(value).getRectValue();
 
@@ -129,7 +129,7 @@ static FontDescription::GenericFamilyType convertGenericFamily(CSSValueID valueI
     }
 }
 
-static bool convertFontFamilyName(StyleResolverState& state, CSSPrimitiveValue primitiveValue,
+static bool convertFontFamilyName(StyleResolverState& state, const CSSPrimitiveValue& primitiveValue,
     FontDescription::GenericFamilyType& genericFamily, AtomicString& familyName)
 {
     if (primitiveValue.isCustomIdent()) {
@@ -143,7 +143,7 @@ static bool convertFontFamilyName(StyleResolverState& state, CSSPrimitiveValue p
     return !familyName.isEmpty();
 }
 
-FontDescription::FamilyDescription StyleBuilderConverter::convertFontFamily(StyleResolverState& state, CSSValue value)
+FontDescription::FamilyDescription StyleBuilderConverter::convertFontFamily(StyleResolverState& state, const CSSValue& value)
 {
     ASSERT(value.isValueList());
 
@@ -174,7 +174,7 @@ FontDescription::FamilyDescription StyleBuilderConverter::convertFontFamily(Styl
     return desc;
 }
 
-PassRefPtr<FontFeatureSettings> StyleBuilderConverter::convertFontFeatureSettings(StyleResolverState& state, CSSValue value)
+PassRefPtr<FontFeatureSettings> StyleBuilderConverter::convertFontFeatureSettings(StyleResolverState& state, const CSSValue& value)
 {
     if (value.isPrimitiveValue() && toCSSPrimitiveValue(value).getValueID() == CSSValueNormal)
         return FontBuilder::initialFeatureSettings();
@@ -189,7 +189,7 @@ PassRefPtr<FontFeatureSettings> StyleBuilderConverter::convertFontFeatureSetting
     return settings;
 }
 
-static float computeFontSize(StyleResolverState& state, CSSPrimitiveValue primitiveValue, const FontDescription::Size& parentSize)
+static float computeFontSize(StyleResolverState& state, const CSSPrimitiveValue& primitiveValue, const FontDescription::Size& parentSize)
 {
     float em = state.parentStyle()->specifiedFontSize();
     float rem = state.rootElementStyle() ? state.rootElementStyle()->specifiedFontSize() : 1.0f;
@@ -206,9 +206,9 @@ static float computeFontSize(StyleResolverState& state, CSSPrimitiveValue primit
     return 0;
 }
 
-FontDescription::Size StyleBuilderConverter::convertFontSize(StyleResolverState& state, CSSValue value)
+FontDescription::Size StyleBuilderConverter::convertFontSize(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
 
     FontDescription::Size parentSize(0, 0.0f, false);
 
@@ -245,9 +245,9 @@ FontDescription::Size StyleBuilderConverter::convertFontSize(StyleResolverState&
     return FontDescription::Size(0, computeFontSize(state, primitiveValue, parentSize), parentIsAbsoluteSize || !primitiveValue.isFontRelativeLength());
 }
 
-float StyleBuilderConverter::convertFontSizeAdjust(StyleResolverState& state, CSSValue value)
+float StyleBuilderConverter::convertFontSizeAdjust(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue.getValueID() == CSSValueNone)
         return FontBuilder::initialSizeAdjust();
 
@@ -255,9 +255,9 @@ float StyleBuilderConverter::convertFontSizeAdjust(StyleResolverState& state, CS
     return primitiveValue.getFloatValue();
 }
 
-FontWeight StyleBuilderConverter::convertFontWeight(StyleResolverState& state, CSSValue value)
+FontWeight StyleBuilderConverter::convertFontWeight(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     switch (primitiveValue.getValueID()) {
     case CSSValueBolder:
         return FontDescription::bolderWeight(state.parentStyle()->fontDescription().weight());
@@ -268,14 +268,14 @@ FontWeight StyleBuilderConverter::convertFontWeight(StyleResolverState& state, C
     }
 }
 
-FontDescription::VariantLigatures StyleBuilderConverter::convertFontVariantLigatures(StyleResolverState&, CSSValue value)
+FontDescription::VariantLigatures StyleBuilderConverter::convertFontVariantLigatures(StyleResolverState&, const CSSValue& value)
 {
     if (value.isValueList()) {
         FontDescription::VariantLigatures ligatures;
         CSSValueList& valueList = toCSSValueList(value);
         for (size_t i = 0; i < valueList.length(); ++i) {
-            CSSValue item = valueList.item(i);
-            CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(item);
+            const CSSValue& item = valueList.item(i);
+            const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(item);
             switch (primitiveValue.getValueID()) {
             case CSSValueNoCommonLigatures:
                 ligatures.common = FontDescription::DisabledLigaturesState;
@@ -314,12 +314,12 @@ FontDescription::VariantLigatures StyleBuilderConverter::convertFontVariantLigat
     return FontDescription::VariantLigatures();
 }
 
-EGlyphOrientation StyleBuilderConverter::convertGlyphOrientation(StyleResolverState&, CSSValue value)
+EGlyphOrientation StyleBuilderConverter::convertGlyphOrientation(StyleResolverState&, const CSSValue& value)
 {
     if (!value.isPrimitiveValue())
         return GO_0DEG;
 
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue.primitiveType() != CSSPrimitiveValue::CSS_DEG)
         return GO_0DEG;
 
@@ -334,17 +334,17 @@ EGlyphOrientation StyleBuilderConverter::convertGlyphOrientation(StyleResolverSt
     return GO_270DEG;
 }
 
-StyleSelfAlignmentData StyleBuilderConverter::convertSelfOrDefaultAlignmentData(StyleResolverState&, CSSValue value)
+StyleSelfAlignmentData StyleBuilderConverter::convertSelfOrDefaultAlignmentData(StyleResolverState&, const CSSValue& value)
 {
     StyleSelfAlignmentData alignmentData = ComputedStyle::initialSelfAlignment();
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (Pair* pairValue = primitiveValue.getPairValue()) {
-        if (toCSSPrimitiveValue(*pairValue->first()).getValueID() == CSSValueLegacy) {
+        if (pairValue->first().getValueID() == CSSValueLegacy) {
             alignmentData.setPositionType(LegacyPosition);
-            alignmentData.setPosition(toCSSPrimitiveValue(*pairValue->second()));
+            alignmentData.setPosition(pairValue->second());
         } else {
-            alignmentData.setPosition(toCSSPrimitiveValue(*pairValue->first()));
-            alignmentData.setOverflow(toCSSPrimitiveValue(*pairValue->second()));
+            alignmentData.setPosition(pairValue->first());
+            alignmentData.setOverflow(pairValue->second());
         }
     } else {
         alignmentData.setPosition(primitiveValue);
@@ -352,7 +352,7 @@ StyleSelfAlignmentData StyleBuilderConverter::convertSelfOrDefaultAlignmentData(
     return alignmentData;
 }
 
-StyleContentAlignmentData StyleBuilderConverter::convertContentAlignmentData(StyleResolverState&, CSSValue value)
+StyleContentAlignmentData StyleBuilderConverter::convertContentAlignmentData(StyleResolverState&, const CSSValue& value)
 {
     StyleContentAlignmentData alignmentData = ComputedStyle::initialContentAlignment();
     CSSContentDistributionValue& contentValue = toCSSContentDistributionValue(value);
@@ -365,12 +365,12 @@ StyleContentAlignmentData StyleBuilderConverter::convertContentAlignmentData(Sty
     return alignmentData;
 }
 
-GridAutoFlow StyleBuilderConverter::convertGridAutoFlow(StyleResolverState&, CSSValue value)
+GridAutoFlow StyleBuilderConverter::convertGridAutoFlow(StyleResolverState&, const CSSValue& value)
 {
     CSSValueList& list = toCSSValueList(value);
 
     ASSERT(list.length() >= 1);
-    CSSPrimitiveValue first = toCSSPrimitiveValue(list.item(0));
+    const CSSPrimitiveValue& first = toCSSPrimitiveValue(list.item(0));
     NullableCSSValue second = list.length() == 2 ? NullableCSSValue(list.item(1)) : nullptr;
 
     switch (first.getValueID()) {
@@ -392,7 +392,7 @@ GridAutoFlow StyleBuilderConverter::convertGridAutoFlow(StyleResolverState&, CSS
     }
 }
 
-GridPosition StyleBuilderConverter::convertGridPosition(StyleResolverState&, CSSValue value)
+GridPosition StyleBuilderConverter::convertGridPosition(StyleResolverState&, const CSSValue& value)
 {
     // We accept the specification's grammar:
     // 'auto' | [ <integer> || <custom-ident> ] | [ span && [ <integer> || <custom-ident> ] ] | <custom-ident>
@@ -400,7 +400,7 @@ GridPosition StyleBuilderConverter::convertGridPosition(StyleResolverState&, CSS
     GridPosition position;
 
     if (value.isPrimitiveValue()) {
-        CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+        const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
         // We translate <custom-ident> to <string> during parsing as it
         // makes handling it more simple.
         if (primitiveValue.isCustomIdent()) {
@@ -448,7 +448,7 @@ GridPosition StyleBuilderConverter::convertGridPosition(StyleResolverState&, CSS
     return position;
 }
 
-GridTrackSize StyleBuilderConverter::convertGridTrackSize(StyleResolverState& state, CSSValue value)
+GridTrackSize StyleBuilderConverter::convertGridTrackSize(StyleResolverState& state, const CSSValue& value)
 {
     if (value.isPrimitiveValue())
         return GridTrackSize(convertGridTrackBreadth(state, toCSSPrimitiveValue(value)));
@@ -460,11 +460,11 @@ GridTrackSize StyleBuilderConverter::convertGridTrackSize(StyleResolverState& st
     return GridTrackSize(minTrackBreadth, maxTrackBreadth);
 }
 
-bool StyleBuilderConverter::convertGridTrackList(CSSValue value, Vector<GridTrackSize>& trackSizes, NamedGridLinesMap& namedGridLines, OrderedNamedGridLines& orderedNamedGridLines, StyleResolverState& state)
+bool StyleBuilderConverter::convertGridTrackList(const CSSValue& value, Vector<GridTrackSize>& trackSizes, NamedGridLinesMap& namedGridLines, OrderedNamedGridLines& orderedNamedGridLines, StyleResolverState& state)
 {
     // Handle 'none'.
     if (value.isPrimitiveValue()) {
-        CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+        const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
         return primitiveValue.getValueID() == CSSValueNone;
     }
 
@@ -531,27 +531,27 @@ void StyleBuilderConverter::createImplicitNamedGridLinesFromGridArea(const Named
     }
 }
 
-Length StyleBuilderConverter::convertLength(const StyleResolverState& state, CSSValue value)
+Length StyleBuilderConverter::convertLength(const StyleResolverState& state, const CSSValue& value)
 {
     return toCSSPrimitiveValue(value).convertToLength(state.cssToLengthConversionData());
 }
 
-UnzoomedLength StyleBuilderConverter::convertUnzoomedLength(const StyleResolverState& state, CSSValue value)
+UnzoomedLength StyleBuilderConverter::convertUnzoomedLength(const StyleResolverState& state, const CSSValue& value)
 {
     return UnzoomedLength(toCSSPrimitiveValue(value).convertToLength(state.cssToLengthConversionData().copyWithAdjustedZoom(1.0f)));
 }
 
-Length StyleBuilderConverter::convertLengthOrAuto(const StyleResolverState& state, CSSValue value)
+Length StyleBuilderConverter::convertLengthOrAuto(const StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue.getValueID() == CSSValueAuto)
         return Length(Auto);
     return primitiveValue.convertToLength(state.cssToLengthConversionData());
 }
 
-Length StyleBuilderConverter::convertLengthSizing(StyleResolverState& state, CSSValue value)
+Length StyleBuilderConverter::convertLengthSizing(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     switch (primitiveValue.getValueID()) {
     case CSSValueInvalid:
         return convertLength(state, value);
@@ -577,23 +577,23 @@ Length StyleBuilderConverter::convertLengthSizing(StyleResolverState& state, CSS
     }
 }
 
-Length StyleBuilderConverter::convertLengthMaxSizing(StyleResolverState& state, CSSValue value)
+Length StyleBuilderConverter::convertLengthMaxSizing(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue.getValueID() == CSSValueNone)
         return Length(MaxSizeNone);
     return convertLengthSizing(state, value);
 }
 
-TabSize StyleBuilderConverter::convertLengthOrTabSpaces(StyleResolverState& state, CSSValue value)
+TabSize StyleBuilderConverter::convertLengthOrTabSpaces(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue.isNumber())
         return TabSize(primitiveValue.getIntValue());
     return TabSize(primitiveValue.computeLength<float>(state.cssToLengthConversionData()));
 }
 
-LineBoxContain StyleBuilderConverter::convertLineBoxContain(StyleResolverState&, CSSValue value)
+LineBoxContain StyleBuilderConverter::convertLineBoxContain(StyleResolverState&, const CSSValue& value)
 {
     if (value.isPrimitiveValue()) {
         ASSERT(toCSSPrimitiveValue(value).getValueID() == CSSValueNone);
@@ -611,9 +611,9 @@ static CSSToLengthConversionData lineHeightToLengthConversionData(StyleResolverS
     return state.cssToLengthConversionData().copyWithAdjustedZoom(multiplier);
 }
 
-Length StyleBuilderConverter::convertLineHeight(StyleResolverState& state, CSSValue value)
+Length StyleBuilderConverter::convertLineHeight(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
 
     if (primitiveValue.isLength())
         return primitiveValue.computeLength<Length>(lineHeightToLengthConversionData(state));
@@ -630,9 +630,9 @@ Length StyleBuilderConverter::convertLineHeight(StyleResolverState& state, CSSVa
     return ComputedStyle::initialLineHeight();
 }
 
-float StyleBuilderConverter::convertNumberOrPercentage(StyleResolverState& state, CSSValue value)
+float StyleBuilderConverter::convertNumberOrPercentage(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     ASSERT(primitiveValue.isNumber() || primitiveValue.isPercentage());
     if (primitiveValue.isNumber())
         return primitiveValue.getFloatValue();
@@ -640,37 +640,37 @@ float StyleBuilderConverter::convertNumberOrPercentage(StyleResolverState& state
 }
 
 template <CSSValueID cssValueFor0, CSSValueID cssValueFor100>
-static Length convertPositionLength(StyleResolverState& state, CSSPrimitiveValue primitiveValue)
+static Length convertPositionLength(StyleResolverState& state, const CSSPrimitiveValue& primitiveValue)
 {
     if (Pair* pair = primitiveValue.getPairValue()) {
-        Length length = StyleBuilderConverter::convertLength(state, CSSValue(*pair->second()));
-        if (toCSSPrimitiveValue(*pair->first()).getValueID() == cssValueFor0)
+        Length length = StyleBuilderConverter::convertLength(state, pair->second());
+        if (pair->first().getValueID() == cssValueFor0)
             return length;
-        ASSERT(toCSSPrimitiveValue(*pair->first()).getValueID() == cssValueFor100);
+        ASSERT(pair->first().getValueID() == cssValueFor100);
         return length.subtractFromOneHundredPercent();
     }
 
     return StyleBuilderConverter::convertLength(state, primitiveValue);
 }
 
-LengthPoint StyleBuilderConverter::convertPosition(StyleResolverState& state, CSSValue value)
+LengthPoint StyleBuilderConverter::convertPosition(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     Pair* pair = primitiveValue.getPairValue();
     return LengthPoint(
-        convertPositionLength<CSSValueLeft, CSSValueRight>(state, toCSSPrimitiveValue(*pair->first())),
-        convertPositionLength<CSSValueTop, CSSValueBottom>(state, toCSSPrimitiveValue(*pair->second()))
+        convertPositionLength<CSSValueLeft, CSSValueRight>(state, pair->first()),
+        convertPositionLength<CSSValueTop, CSSValueBottom>(state, pair->second())
     );
 }
 
-static float convertPerspectiveLength(StyleResolverState& state, CSSPrimitiveValue primitiveValue)
+static float convertPerspectiveLength(StyleResolverState& state, const CSSPrimitiveValue& primitiveValue)
 {
     return std::max(primitiveValue.computeLength<float>(state.cssToLengthConversionData()), 0.0f);
 }
 
-float StyleBuilderConverter::convertPerspective(StyleResolverState& state, CSSValue value)
+float StyleBuilderConverter::convertPerspective(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
 
     if (primitiveValue.getValueID() == CSSValueNone)
         return ComputedStyle::initialPerspective();
@@ -678,7 +678,7 @@ float StyleBuilderConverter::convertPerspective(StyleResolverState& state, CSSVa
 }
 
 template <CSSValueID cssValueFor0, CSSValueID cssValueFor100>
-static Length convertOriginLength(StyleResolverState& state, CSSPrimitiveValue primitiveValue)
+static Length convertOriginLength(StyleResolverState& state, const CSSPrimitiveValue& primitiveValue)
 {
     if (primitiveValue.isValueID()) {
         switch (primitiveValue.getValueID()) {
@@ -696,13 +696,13 @@ static Length convertOriginLength(StyleResolverState& state, CSSPrimitiveValue p
     return StyleBuilderConverter::convertLength(state, CSSValue(primitiveValue));
 }
 
-LengthPoint StyleBuilderConverter::convertPerspectiveOrigin(StyleResolverState& state, CSSValue value)
+LengthPoint StyleBuilderConverter::convertPerspectiveOrigin(StyleResolverState& state, const CSSValue& value)
 {
     CSSValueList& list = toCSSValueList(value);
     ASSERT(list.length() == 2);
 
-    CSSPrimitiveValue primitiveValueX = toCSSPrimitiveValue(list.item(0));
-    CSSPrimitiveValue primitiveValueY = toCSSPrimitiveValue(list.item(1));
+    const CSSPrimitiveValue& primitiveValueX = toCSSPrimitiveValue(list.item(0));
+    const CSSPrimitiveValue& primitiveValueY = toCSSPrimitiveValue(list.item(1));
 
     return LengthPoint(
         convertOriginLength<CSSValueLeft, CSSValueRight>(state, primitiveValueX),
@@ -710,7 +710,7 @@ LengthPoint StyleBuilderConverter::convertPerspectiveOrigin(StyleResolverState&
     );
 }
 
-EPaintOrder StyleBuilderConverter::convertPaintOrder(StyleResolverState&, CSSValue cssPaintOrder)
+EPaintOrder StyleBuilderConverter::convertPaintOrder(StyleResolverState&, const CSSValue& cssPaintOrder)
 {
     if (cssPaintOrder.isValueList()) {
         int paintOrder = 0;
@@ -740,7 +740,7 @@ EPaintOrder StyleBuilderConverter::convertPaintOrder(StyleResolverState&, CSSVal
     return PO_NORMAL;
 }
 
-Length StyleBuilderConverter::convertQuirkyLength(StyleResolverState& state, CSSValue value)
+Length StyleBuilderConverter::convertQuirkyLength(StyleResolverState& state, const CSSValue& value)
 {
     Length length = convertLengthOrAuto(state, value);
     // This is only for margins which use __qem
@@ -748,14 +748,14 @@ Length StyleBuilderConverter::convertQuirkyLength(StyleResolverState& state, CSS
     return length;
 }
 
-PassRefPtr<QuotesData> StyleBuilderConverter::convertQuotes(StyleResolverState&, CSSValue value)
+PassRefPtr<QuotesData> StyleBuilderConverter::convertQuotes(StyleResolverState&, const CSSValue& value)
 {
     if (value.isValueList()) {
         CSSValueList& list = toCSSValueList(value);
         RefPtr<QuotesData> quotes = QuotesData::create();
         for (size_t i = 0; i < list.length(); i += 2) {
-            CSSValue first = list.item(i);
-            CSSValue second = list.item(i + 1);
+            const CSSValue& first = list.item(i);
+            const CSSValue& second = list.item(i + 1);
             String startQuote = toCSSPrimitiveValue(first).getStringValue();
             String endQuote = toCSSPrimitiveValue(second).getStringValue();
             quotes->addPair(std::make_pair(startQuote, endQuote));
@@ -766,12 +766,12 @@ PassRefPtr<QuotesData> StyleBuilderConverter::convertQuotes(StyleResolverState&,
     return QuotesData::create();
 }
 
-LengthSize StyleBuilderConverter::convertRadius(StyleResolverState& state, CSSValue value)
+LengthSize StyleBuilderConverter::convertRadius(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     Pair* pair = primitiveValue.getPairValue();
-    Length radiusWidth = toCSSPrimitiveValue(*pair->first()).convertToLength(state.cssToLengthConversionData());
-    Length radiusHeight = toCSSPrimitiveValue(*pair->second()).convertToLength(state.cssToLengthConversionData());
+    Length radiusWidth = pair->first().convertToLength(state.cssToLengthConversionData());
+    Length radiusHeight = pair->second().convertToLength(state.cssToLengthConversionData());
     float width = radiusWidth.value();
     float height = radiusHeight.value();
     ASSERT(width >= 0 && height >= 0);
@@ -780,7 +780,7 @@ LengthSize StyleBuilderConverter::convertRadius(StyleResolverState& state, CSSVa
     return LengthSize(radiusWidth, radiusHeight);
 }
 
-PassRefPtr<ShadowList> StyleBuilderConverter::convertShadow(StyleResolverState& state, CSSValue value)
+PassRefPtr<ShadowList> StyleBuilderConverter::convertShadow(StyleResolverState& state, const CSSValue& value)
 {
     if (value.isPrimitiveValue()) {
         ASSERT(toCSSPrimitiveValue(value).getValueID() == CSSValueNone);
@@ -805,7 +805,7 @@ PassRefPtr<ShadowList> StyleBuilderConverter::convertShadow(StyleResolverState&
     return ShadowList::adopt(shadows);
 }
 
-PassRefPtr<ShapeValue> StyleBuilderConverter::convertShapeValue(StyleResolverState& state, CSSValue value)
+PassRefPtr<ShapeValue> StyleBuilderConverter::convertShapeValue(StyleResolverState& state, const CSSValue& value)
 {
     if (value.isPrimitiveValue()) {
         ASSERT(toCSSPrimitiveValue(value).getValueID() == CSSValueNone);
@@ -819,7 +819,7 @@ PassRefPtr<ShapeValue> StyleBuilderConverter::convertShapeValue(StyleResolverSta
     CSSBoxType cssBox = BoxMissing;
     CSSValueList& valueList = toCSSValueList(value);
     for (unsigned i = 0; i < valueList.length(); ++i) {
-        CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(valueList.item(i));
+        const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(valueList.item(i));
         if (primitiveValue.isShape())
             shape = basicShapeForValue(state, primitiveValue.getShapeValue());
         else
@@ -833,15 +833,15 @@ PassRefPtr<ShapeValue> StyleBuilderConverter::convertShapeValue(StyleResolverSta
     return ShapeValue::createBoxShapeValue(cssBox);
 }
 
-float StyleBuilderConverter::convertSpacing(StyleResolverState& state, CSSValue value)
+float StyleBuilderConverter::convertSpacing(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue.getValueID() == CSSValueNormal)
         return 0;
     return primitiveValue.computeLength<float>(state.cssToLengthConversionData());
 }
 
-PassRefPtr<SVGDashArray> StyleBuilderConverter::convertStrokeDasharray(StyleResolverState& state, CSSValue value)
+PassRefPtr<SVGDashArray> StyleBuilderConverter::convertStrokeDasharray(StyleResolverState& state, const CSSValue& value)
 {
     if (!value.isValueList())
         return SVGComputedStyle::initialStrokeDashArray();
@@ -851,7 +851,7 @@ PassRefPtr<SVGDashArray> StyleBuilderConverter::convertStrokeDasharray(StyleReso
     RefPtr<SVGDashArray> array = SVGDashArray::create();
     size_t length = dashes.length();
     for (size_t i = 0; i < length; ++i) {
-        CSSValue currValue = dashes.item(i);
+        const CSSValue& currValue = dashes.item(i);
         if (!currValue.isPrimitiveValue())
             continue;
 
@@ -861,17 +861,17 @@ PassRefPtr<SVGDashArray> StyleBuilderConverter::convertStrokeDasharray(StyleReso
     return array.release();
 }
 
-StyleColor StyleBuilderConverter::convertStyleColor(StyleResolverState& state, CSSValue value, bool forVisitedLink)
+StyleColor StyleBuilderConverter::convertStyleColor(StyleResolverState& state, const CSSValue& value, bool forVisitedLink)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue.getValueID() == CSSValueCurrentcolor)
         return StyleColor::currentColor();
     return state.document().textLinkColors().colorFromPrimitiveValue(primitiveValue, Color(), forVisitedLink);
 }
 
-float StyleBuilderConverter::convertTextStrokeWidth(StyleResolverState& state, CSSValue value)
+float StyleBuilderConverter::convertTextStrokeWidth(StyleResolverState& state, const CSSValue& value)
 {
-    CSSPrimitiveValue primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue& primitiveValue = toCSSPrimitiveValue(value);
     if (primitiveValue.getValueID()) {
         float multiplier = convertLineWidth<float>(state, value);
         return CSSPrimitiveValue::create(multiplier / 48, CSSPrimitiveValue::CSS_EMS).computeLength<float>(state.cssToLengthConversionData());
@@ -879,13 +879,13 @@ float StyleBuilderConverter::convertTextStrokeWidth(StyleResolverState& state, C
     return primitiveValue.computeLength<float>(state.cssToLengthConversionData());
 }
 
-TransformOrigin StyleBuilderConverter::convertTransformOrigin(StyleResolverState& state, CSSValue value)
+TransformOrigin StyleBuilderConverter::convertTransformOrigin(StyleResolverState& state, const CSSValue& value)
 {
     CSSValueList& list = toCSSValueList(value);
     ASSERT(list.length() == 3);
 
-    CSSPrimitiveValue primitiveValueX = toCSSPrimitiveValue(list.item(0));
-    CSSPrimitiveValue primitiveValueY = toCSSPrimitiveValue(list.item(1));
+    const CSSPrimitiveValue& primitiveValueX = toCSSPrimitiveValue(list.item(0));
+    const CSSPrimitiveValue& primitiveValueY = toCSSPrimitiveValue(list.item(1));
 
     return TransformOrigin(
         convertOriginLength<CSSValueLeft, CSSValueRight>(state, primitiveValueX),
@@ -894,7 +894,7 @@ TransformOrigin StyleBuilderConverter::convertTransformOrigin(StyleResolverState
     );
 }
 
-ScrollSnapPoints StyleBuilderConverter::convertSnapPoints(StyleResolverState& state, CSSValue value)
+ScrollSnapPoints StyleBuilderConverter::convertSnapPoints(StyleResolverState& state, const CSSValue& value)
 {
     // Handles: none | repeat(<length>)
     ScrollSnapPoints points;
@@ -911,7 +911,7 @@ ScrollSnapPoints StyleBuilderConverter::convertSnapPoints(StyleResolverState& st
     return points;
 }
 
-Vector<LengthPoint> StyleBuilderConverter::convertSnapCoordinates(StyleResolverState& state, CSSValue value)
+Vector<LengthPoint> StyleBuilderConverter::convertSnapCoordinates(StyleResolverState& state, const CSSValue& value)
 {
     // Handles: none | <position>#
     Vector<LengthPoint> coordinates;
@@ -928,7 +928,7 @@ Vector<LengthPoint> StyleBuilderConverter::convertSnapCoordinates(StyleResolverS
     return coordinates;
 }
 
-PassRefPtr<TranslateTransformOperation> StyleBuilderConverter::convertTranslate(StyleResolverState& state, CSSValue value)
+PassRefPtr<TranslateTransformOperation> StyleBuilderConverter::convertTranslate(StyleResolverState& state, const CSSValue& value)
 {
     CSSValueList& list = toCSSValueList(value);
     ASSERT(list.length() <= 3);
@@ -943,7 +943,7 @@ PassRefPtr<TranslateTransformOperation> StyleBuilderConverter::convertTranslate(
     return TranslateTransformOperation::create(tx, ty, tz, TransformOperation::Translate3D);
 }
 
-PassRefPtr<RotateTransformOperation> StyleBuilderConverter::convertRotate(StyleResolverState& state, CSSValue value)
+PassRefPtr<RotateTransformOperation> StyleBuilderConverter::convertRotate(StyleResolverState& state, const CSSValue& value)
 {
     CSSValueList& list = toCSSValueList(value);
     ASSERT(list.length() == 1 || list.length() == 4);
@@ -960,7 +960,7 @@ PassRefPtr<RotateTransformOperation> StyleBuilderConverter::convertRotate(StyleR
     return RotateTransformOperation::create(x, y, z, angle, TransformOperation::Rotate3D);
 }
 
-PassRefPtr<ScaleTransformOperation> StyleBuilderConverter::convertScale(StyleResolverState& state, CSSValue value)
+PassRefPtr<ScaleTransformOperation> StyleBuilderConverter::convertScale(StyleResolverState& state, const CSSValue& value)
 {
     CSSValueList& list = toCSSValueList(value);
     ASSERT(list.length() <= 3);