CSSValue Immediates: Replace CSSPrimitiveValue usage with const references

Source/core/css/Pair.h

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 19 matching lines @@
 namespace blink {
 
 // A primitive value representing a pair.  This is useful for properties like border-radius, background-size/position,
 // and border-spacing (all of which are space-separated sets of two values).  At the moment we are only using it for
 // border-radius and background-size, but (FIXME) border-spacing and background-position could be converted over to use
 // it (eliminating some extra -webkit- internal properties).
 class CORE_EXPORT Pair final : public RefCountedWillBeGarbageCollectedFinalized<Pair> {
 public:
     enum IdenticalValuesPolicy { DropIdenticalValues, KeepIdenticalValues };
 
-    static PassRefPtrWillBeRawPtr<Pair> create(CSSPrimitiveValue first, CSSPrimitiveValue second,
+    static PassRefPtrWillBeRawPtr<Pair> create(const CSSPrimitiveValue& first, const CSSPrimitiveValue& second,
         IdenticalValuesPolicy identicalValuesPolicy)
     {
         return adoptRefWillBeNoop(new Pair(first, second, identicalValuesPolicy));
     }
 
-    NullableCSSValue first() const { return m_first; }
-    NullableCSSValue second() const { return m_second; }
+    const CSSPrimitiveValue& first() const { return toCSSPrimitiveValue(m_first); }
+    const CSSPrimitiveValue& second() const { return toCSSPrimitiveValue(m_second); }
 
     String cssText() const
     {
-        return generateCSSString(first()->cssText(), second()->cssText(), m_identicalValuesPolicy);
+        return generateCSSString(first().cssText(), second().cssText(), m_identicalValuesPolicy);
     }
 
     bool equals(const Pair& other) const
     {
-        return m_first == other.m_first
-            && m_second == other.m_second
+        return m_first.equals(other.m_first)
+            && m_second.equals(other.m_second)
             && m_identicalValuesPolicy == other.m_identicalValuesPolicy;
     }
 
     DECLARE_TRACE();
 
 private:
-    Pair(CSSPrimitiveValue first, CSSPrimitiveValue second, IdenticalValuesPolicy identicalValuesPolicy)
+    Pair(const CSSPrimitiveValue& first, const CSSPrimitiveValue& second, IdenticalValuesPolicy identicalValuesPolicy)
         : m_first(first)
         , m_second(second)
         , m_identicalValuesPolicy(identicalValuesPolicy) { }
 
     static String generateCSSString(const String& first, const String& second, IdenticalValuesPolicy identicalValuesPolicy)
     {
         if (identicalValuesPolicy == DropIdenticalValues && first == second)
             return first;
         return first + ' ' + second;
     }
 
-    NullableCSSValue m_first;
-    NullableCSSValue m_second;
+    CSSValue m_first;
+    CSSValue m_second;
     IdenticalValuesPolicy m_identicalValuesPolicy;
 };
 
 } // namespace
 
 #endif