CSSValue Immediates: Replace CSSPrimitiveValue usage with const references

Source/core/animation/animatable/AnimatableUnknown.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 24 matching lines @@
 #include "core/animation/animatable/AnimatableValue.h"
 #include "core/css/CSSValue.h"
 #include "core/css/CSSValuePool.h"
 
 namespace blink {
 
 class AnimatableUnknown final : public AnimatableValue {
 public:
     virtual ~AnimatableUnknown() { }
 
-    static PassRefPtrWillBeRawPtr<AnimatableUnknown> create(CSSPrimitiveValue value)
+    static PassRefPtrWillBeRawPtr<AnimatableUnknown> create(const CSSPrimitiveValue& value)
     {
         return adoptRefWillBeNoop(new AnimatableUnknown(value));
     }
     static PassRefPtrWillBeRawPtr<AnimatableUnknown> create(CSSValueID value)
     {
         return adoptRefWillBeNoop(new AnimatableUnknown(cssValuePool().createIdentifierValue(value)));
     }
 
-    CSSPrimitiveValue toCSSValue() const { return toCSSPrimitiveValue(m_value); }
+    const CSSPrimitiveValue& toCSSValue() const { return toCSSPrimitiveValue(m_value); }
     CSSValueID toCSSValueID() const { return toCSSPrimitiveValue(m_value).getValueID(); }
 
     DEFINE_INLINE_VIRTUAL_TRACE()
     {
         visitor->trace(m_value);
         AnimatableValue::trace(visitor);
     }
 
 protected:
     virtual PassRefPtrWillBeRawPtr<AnimatableValue> interpolateTo(const AnimatableValue* value, double fraction) const override
     {
         return defaultInterpolateTo(this, value, fraction);
     }
 
     virtual bool usesDefaultInterpolationWith(const AnimatableValue*) const override { return true; }
 
 private:
-    explicit AnimatableUnknown(CSSPrimitiveValue value)
+    explicit AnimatableUnknown(const CSSPrimitiveValue& value)
         : m_value(value)
     {
     }
     virtual AnimatableType type() const override { return TypeUnknown; }
     virtual bool equalTo(const AnimatableValue*) const override;
 
     const CSSValue m_value;
 };
 
 DEFINE_ANIMATABLE_VALUE_TYPE_CASTS(AnimatableUnknown, isUnknown());
 
 inline bool AnimatableUnknown::equalTo(const AnimatableValue* value) const
 {
     const AnimatableUnknown* unknown = toAnimatableUnknown(value);
     return m_value.ptrEquals(unknown->m_value) || m_value.equals(unknown->m_value);
 }
 
 } // namespace blink
 
 #endif // AnimatableUnknown_h