Allow interpolation of background-size values with keywords in CSS Animations

third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.h

Index: third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.h
diff --git a/third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.h b/third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.h
new file mode 100644
index 0000000000000000000000000000000000000000..6f3050438e137941bfe0e5f823b18d29ff56d57f
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+++ b/third_party/WebKit/Source/core/animation/SizeInterpolationFunctions.h
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+// 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.
+
+#ifndef SizeInterpolationFunctions_h
+#define SizeInterpolationFunctions_h
+
+#include "core/animation/InterpolationValue.h"
+#include "core/animation/PairwiseInterpolationValue.h"
+#include "core/style/FillLayer.h"
+#include <memory>
+
+namespace blink {
+
+class CSSToLengthConversionData;
+class CSSValue;
+
+class SizeInterpolationFunctions {
+    STATIC_ONLY(SizeInterpolationFunctions);
+public:
+    static InterpolationValue convertFillSizeSide(const FillSize&, float zoom, bool convertWidth);
+    static InterpolationValue maybeConvertCSSSizeSide(const CSSValue&, bool convertWidth);
+    static PairwiseInterpolationValue maybeMergeSingles(InterpolationValue&& start, InterpolationValue&& end);
+    static InterpolationValue createNeutralValue(const NonInterpolableValue*);
+    static bool nonInterpolableValuesAreCompatible(const NonInterpolableValue*, const NonInterpolableValue*);
+    static void composite(std::unique_ptr<InterpolableValue>&, RefPtr<NonInterpolableValue>&, double underlyingFraction, const InterpolableValue&, const NonInterpolableValue*);
+    static FillSize createFillSize(const InterpolableValue& interpolableValueA, const NonInterpolableValue* nonInterpolableValueA, const InterpolableValue& interpolableValueB, const NonInterpolableValue* nonInterpolableValueB, const CSSToLengthConversionData&);
+};
+
+} // namespace blink
+
+#endif // SizeInterpolationFunctions_h