CSSValue Immediates: Replace CSSPrimitiveValue usage with const references

Source/core/animation/LengthPairStyleInterpolationTest.cpp

Index: Source/core/animation/LengthPairStyleInterpolationTest.cpp
diff --git a/Source/core/animation/LengthPairStyleInterpolationTest.cpp b/Source/core/animation/LengthPairStyleInterpolationTest.cpp
index 1671d5b3b85507cd8457469575a78410b4b844c8..3e24621199aad831d9b2a6af24ee1e0c72a90379 100644
--- a/Source/core/animation/LengthPairStyleInterpolationTest.cpp
+++ b/Source/core/animation/LengthPairStyleInterpolationTest.cpp
@@ -39,11 +39,11 @@ protected:
         Pair* pair = toCSSPrimitiveValue(value).getPairValue();
         ASSERT_TRUE(pair);
 
-        EXPECT_EQ(toCSSPrimitiveValue(*pair->first()).getDoubleValue(), first);
-        EXPECT_EQ(toCSSPrimitiveValue(*pair->second()).getDoubleValue(), second);
+        EXPECT_EQ(pair->first().getDoubleValue(), first);
+        EXPECT_EQ(pair->second().getDoubleValue(), second);
 
-        EXPECT_EQ(toCSSPrimitiveValue(*pair->first()).primitiveType(), unitType);
-        EXPECT_EQ(toCSSPrimitiveValue(*pair->second()).primitiveType(), unitType);
+        EXPECT_EQ(pair->first().primitiveType(), unitType);
+        EXPECT_EQ(pair->second().primitiveType(), unitType);
     }
 };