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

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

Index: third_party/WebKit/Source/core/animation/CSSPositionAxisListInterpolationType.cpp
diff --git a/third_party/WebKit/Source/core/animation/CSSPositionAxisListInterpolationType.cpp b/third_party/WebKit/Source/core/animation/CSSPositionAxisListInterpolationType.cpp
deleted file mode 100644
index 93d79823aaaa3af4b6158a7f75e8120fd7e84fad..0000000000000000000000000000000000000000
--- a/third_party/WebKit/Source/core/animation/CSSPositionAxisListInterpolationType.cpp
+++ /dev/null
@@ -1,42 +0,0 @@
-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "core/animation/CSSPositionAxisListInterpolationType.h"
-
-#include "core/animation/CSSLengthInterpolationType.h"
-#include "core/animation/ListInterpolationFunctions.h"
-#include "core/css/CSSPrimitiveValue.h"
-#include "core/css/CSSValueList.h"
-#include "core/css/CSSValuePair.h"
-
-namespace blink {
-
-static InterpolationValue convertPositionAxisCSSValue(const CSSValue& value)
-{
-    if (!value.isValuePair())
-        return CSSLengthInterpolationType::maybeConvertCSSValue(value);
-
-    const CSSValuePair& pair = toCSSValuePair(value);
-    InterpolationValue result = CSSLengthInterpolationType::maybeConvertCSSValue(pair.second());
-    CSSValueID side = toCSSPrimitiveValue(pair.first()).getValueID();
-    if (side == CSSValueRight || side == CSSValueBottom)
-        CSSLengthInterpolationType::subtractFromOneHundredPercent(result);
-    return result;
-}
-
-InterpolationValue CSSPositionAxisListInterpolationType::maybeConvertValue(const CSSValue& value, const StyleResolverState&, ConversionCheckers&) const
-{
-    if (!value.isBaseValueList()) {
-        return ListInterpolationFunctions::createList(1, [&value](size_t) {
-            return convertPositionAxisCSSValue(value);
-        });
-    }
-
-    const CSSValueList& list = toCSSValueList(value);
-    return ListInterpolationFunctions::createList(list.length(), [&list](size_t index) {
-        return convertPositionAxisCSSValue(*list.item(index));
-    });
-}
-
-} // namespace blink