Split CSSPrimitiveValue into CSSPrimitiveValue and CSSIdentifierValue

third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.cpp

Index: third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.cpp
diff --git a/third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.cpp b/third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.cpp
index 5998eba4b788c1297d9f8111c15d830b81c50bf9..6b5783843ed14d9f993cde53d74336ee8dd8020a 100644
--- a/third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.cpp
+++ b/third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.cpp
@@ -6,6 +6,7 @@
 
 #include "core/animation/LengthInterpolationFunctions.h"
 #include "core/animation/UnderlyingValueOwner.h"
+#include "core/css/CSSIdentifierValue.h"
 #include "core/css/CSSToLengthConversionData.h"
 #include "core/css/CSSValuePair.h"
 
@@ -90,16 +91,15 @@ InterpolationValue SizeInterpolationFunctions::maybeConvertCSSSizeSide(const CSS
     if (value.isValuePair()) {
         const CSSValuePair& pair = toCSSValuePair(value);
         const CSSValue& side = convertWidth ? pair.first() : pair.second();
-        if (side.isPrimitiveValue() && toCSSPrimitiveValue(side).getValueID() == CSSValueAuto)
+        if (side.isIdentifierValue() && toCSSIdentifierValue(side).getValueID() == CSSValueAuto)
             return convertKeyword(CSSValueAuto);
         return wrapConvertedLength(LengthInterpolationFunctions::maybeConvertCSSValue(side));
     }
 
-    if (!value.isPrimitiveValue())
+    if (!value.isIdentifierValue() && !value.isPrimitiveValue())
         return nullptr;
-    CSSValueID keyword = toCSSPrimitiveValue(value).getValueID();
-    if (keyword)
-        return convertKeyword(keyword);
+    if (value.isIdentifierValue())
+        return convertKeyword(toCSSIdentifierValue(value).getValueID());
 
     // A single length is equivalent to "<length> auto".
     if (convertWidth)