Web Animations CSS: Support Animation of StyleImage and LengthBox

Source/core/animation/AnimatableLengthBox.h

Index: Source/core/animation/AnimatableLengthBox.h
diff --git a/Source/core/animation/AnimatableLengthBox.h b/Source/core/animation/AnimatableLengthBox.h
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+/*
+ * Copyright (C) 2013 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef AnimatableLengthBox_h
+#define AnimatableLengthBox_h
+
+#include "core/animation/AnimatableValue.h"
+
+namespace WebCore {
+
+class AnimatableLengthBox : public AnimatableValue {
+public:
+    virtual ~AnimatableLengthBox() { }
+    static PassRefPtr<AnimatableLengthBox> create(PassRefPtr<AnimatableValue> left, PassRefPtr<AnimatableValue> right, PassRefPtr<AnimatableValue> top, PassRefPtr<AnimatableValue> bottom)
+    {
+        return adoptRef(new AnimatableLengthBox(left, right, top, bottom));
+    }
+    const AnimatableValue* left() const { return m_left.get(); }
+    const AnimatableValue* right() const { return m_right.get(); }
+    const AnimatableValue* top() const { return m_top.get(); }
+    const AnimatableValue* bottom() const { return m_bottom.get(); }
+
+protected:
+    virtual PassRefPtr<AnimatableValue> interpolateTo(const AnimatableValue*, double fraction) const OVERRIDE;
+    virtual PassRefPtr<AnimatableValue> addWith(const AnimatableValue*) const OVERRIDE;
+
+private:
+    AnimatableLengthBox(PassRefPtr<AnimatableValue> left, PassRefPtr<AnimatableValue> right, PassRefPtr<AnimatableValue> top, PassRefPtr<AnimatableValue> bottom)
+        : AnimatableValue(TypeLengthBox)
+        , m_left(left)
+        , m_right(right)
+        , m_top(top)
+        , m_bottom(bottom)
+    {
+    }
+
+    RefPtr<AnimatableValue> m_left;
+    RefPtr<AnimatableValue> m_right;
+    RefPtr<AnimatableValue> m_top;
+    RefPtr<AnimatableValue> m_bottom;
+};
+
+inline const AnimatableLengthBox* toAnimatableLengthBox(const AnimatableValue* value)
+{
+    ASSERT_WITH_SECURITY_IMPLICATION(value && value->isLengthBox());
+    return static_cast<const AnimatableLengthBox*>(value);
+}
+
+} // namespace WebCore
+
+#endif // AnimatableLengthBox_h