Use reference for FillLayer if possible

Source/core/animation/css/CSSPropertyEquality.cpp

Index: Source/core/animation/css/CSSPropertyEquality.cpp
diff --git a/Source/core/animation/css/CSSPropertyEquality.cpp b/Source/core/animation/css/CSSPropertyEquality.cpp
index 1c63d3f21e203c51e39373f61ef40a6a1208c6c3..8478e18afdc7f4753fad2a89349bfca5e7fc4416 100644
--- a/Source/core/animation/css/CSSPropertyEquality.cpp
+++ b/Source/core/animation/css/CSSPropertyEquality.cpp
@@ -15,12 +15,10 @@ namespace WebCore {
 namespace {
 
 template <CSSPropertyID property>
-bool fillLayersEqual(const FillLayer* aLayer, const FillLayer* bLayer)
+bool fillLayersEqual(const FillLayer& aLayers, const FillLayer& bLayers)
 {
-    if (aLayer == bLayer)
-        return true;
-    if (!aLayer || !bLayer)
-        return false;
+    const FillLayer* aLayer = &aLayers;
+    const FillLayer* bLayer = &bLayers;
     while (aLayer && bLayer) {
         switch (property) {
         case CSSPropertyBackgroundPositionX: