Change ImmutableStylePropertySet to store const CSSValue

third_party/WebKit/Source/core/css/StylePropertySet.cpp

Index: third_party/WebKit/Source/core/css/StylePropertySet.cpp
diff --git a/third_party/WebKit/Source/core/css/StylePropertySet.cpp b/third_party/WebKit/Source/core/css/StylePropertySet.cpp
index aa0b4b46bf6dd96da9bb7ddb4cc26742c0746923..37ec0ac06ed3f3278fe95fde93bbbda512e01f88 100644
--- a/third_party/WebKit/Source/core/css/StylePropertySet.cpp
+++ b/third_party/WebKit/Source/core/css/StylePropertySet.cpp
@@ -77,7 +77,7 @@ ImmutableStylePropertySet::ImmutableStylePropertySet(const CSSProperty* properti
     : StylePropertySet(cssParserMode, length)
 {
     StylePropertyMetadata* metadataArray = const_cast<StylePropertyMetadata*>(this->metadataArray());
-    Member<CSSValue>* valueArray = const_cast<Member<CSSValue>*>(this->valueArray());
+    Member<const CSSValue>* valueArray = const_cast<Member<const CSSValue>*>(this->valueArray());
     for (unsigned i = 0; i < m_arraySize; ++i) {
         metadataArray[i] = properties[i].metadata();
         valueArray[i] = properties[i].value();
@@ -132,7 +132,7 @@ template CORE_EXPORT int ImmutableStylePropertySet::findPropertyIndex(AtomicStri
 
 DEFINE_TRACE_AFTER_DISPATCH(ImmutableStylePropertySet)
 {
-    const Member<CSSValue>* values = valueArray();
+    const Member<const CSSValue>* values = valueArray();
     for (unsigned i = 0; i < m_arraySize; i++)
         visitor->trace(values[i]);
     StylePropertySet::traceAfterDispatch(visitor);