Web Animations: Introduce ActiveAnimations and AnimationStack

Source/core/animation/AnimationStack.h

Index: Source/core/animation/AnimationStack.h
diff --git a/Source/core/animation/AnimationStack.h b/Source/core/animation/AnimationStack.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 AnimationStack_h
+#define AnimationStack_h
+
+#include "wtf/HashMap.h"
+#include "wtf/RefPtr.h"
+#include "wtf/Vector.h"
+
+namespace WebCore {
+
+class Element;
+class Animation;
+
+class AnimationStack {
+
+public:
+    void add(Animation* animation) { m_activeAnimations.append(animation); }
+    void remove(Animation* animation)
+    {
+        size_t position = m_activeAnimations.find(animation);
+        ASSERT(position != notFound);
+        m_activeAnimations.remove(position);
+    }
+    bool hasActiveAnimations() const { return !m_activeAnimations.isEmpty(); }
+    // FIXME: This should be PassRefPtr<CompositableValue> composite(Element*, CSSPropertyId)
+    const Vector<Animation*>& activeAnimations(const Element* element) const { return m_activeAnimations; }
+
+private:
+    Vector<Animation*> m_activeAnimations;
+};
+
+} // namespace WebCore
+
+#endif