Revert of Web Animations: Remove AnimationPlayer discarding logic

Source/core/animation/SampledEffect.cpp

 // Copyright 2014 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 "config.h"
 #include "core/animation/SampledEffect.h"
 
 #include "core/animation/StyleInterpolation.h"
 
 namespace blink {
 
 SampledEffect::SampledEffect(Animation* animation, PassOwnPtrWillBeRawPtr<WillBeHeapVector<RefPtrWillBeMember<Interpolation> > > interpolations)
     : m_animation(animation)
+#if !ENABLE(OILPAN)
     , m_player(animation->player())
+#endif
     , m_interpolations(interpolations)
     , m_sequenceNumber(animation->player()->sequenceNumber())
     , m_priority(animation->priority())
 {
     ASSERT(m_interpolations && !m_interpolations->isEmpty());
 }
 
+bool SampledEffect::canChange() const
+{
+#if ENABLE(OILPAN)
+    return m_animation;
+#else
+    if (!m_animation)
+        return false;
+    // FIXME: This check won't be needed when Animation and AnimationPlayer are moved to Oilpan.
+    return !m_player->canFree();
+#endif
+}
+
 void SampledEffect::clear()
 {
+#if !ENABLE(OILPAN)
     m_player = nullptr;
+#endif
     m_animation = nullptr;
     m_interpolations->clear();
 }
 
+void SampledEffect::removeReplacedInterpolationsIfNeeded(const BitArray<numCSSProperties>& replacedProperties)
+{
+    if (canChange() && m_animation->isCurrent())
+        return;
+
+    size_t dest = 0;
+    for (auto& interpolation : *m_interpolations) {
+        if (!replacedProperties.get(toStyleInterpolation(interpolation.get())->id()))
+            m_interpolations->at(dest++) = interpolation;
+    }
+    m_interpolations->shrink(dest);
+}
+
 DEFINE_TRACE(SampledEffect)
 {
     visitor->trace(m_animation);
 #if ENABLE(OILPAN)
     visitor->trace(m_interpolations);
 #endif
 }
 
 } // namespace blink