Revert of Add additive animation support for CSS property background-position

third_party/WebKit/Source/core/animation/CSSLengthInterpolationType.cpp

Index: third_party/WebKit/Source/core/animation/CSSLengthInterpolationType.cpp
diff --git a/third_party/WebKit/Source/core/animation/CSSLengthInterpolationType.cpp b/third_party/WebKit/Source/core/animation/CSSLengthInterpolationType.cpp
index 0bb78e13d797d231357a19f72a1ad918151ff686..cdaadc631d0c8a00a7fc42f82ddb8e796a54ccfe 100644
--- a/third_party/WebKit/Source/core/animation/CSSLengthInterpolationType.cpp
+++ b/third_party/WebKit/Source/core/animation/CSSLengthInterpolationType.cpp
@@ -103,18 +103,6 @@
 {
     underlyingInterpolableValue->scaleAndAdd(underlyingFraction, interpolableValue);
     underlyingNonInterpolableValue = CSSLengthNonInterpolableValue::merge(underlyingNonInterpolableValue.get(), nonInterpolableValue);
-}
-
-void CSSLengthInterpolationType::subtractFromOneHundredPercent(InterpolationValue& result)
-{
-    InterpolableList& list = toInterpolableList(*result.interpolableValue);
-    for (size_t i = 0; i < CSSPrimitiveValue::LengthUnitTypeCount; i++) {
-        double value = -toInterpolableNumber(*list.get(i)).value();
-        if (i == CSSPrimitiveValue::UnitTypePercentage)
-            value += 100;
-        toInterpolableNumber(*list.getMutable(i)).set(value);
-    }
-    result.nonInterpolableValue = CSSLengthNonInterpolableValue::create(true);
 }
 
 InterpolationValue CSSLengthInterpolationType::maybeConvertCSSValue(const CSSValue& value)