Store compositor element id in paint properties for animated objects.

third_party/WebKit/Source/platform/graphics/paint/EffectPaintPropertyNode.cpp

 // 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 "platform/graphics/paint/EffectPaintPropertyNode.h"
 
 namespace blink {
 
 EffectPaintPropertyNode* EffectPaintPropertyNode::root() {
   DEFINE_STATIC_REF(
       EffectPaintPropertyNode, root,
       (EffectPaintPropertyNode::create(
           nullptr, TransformPaintPropertyNode::root(),
           ClipPaintPropertyNode::root(), CompositorFilterOperations(), 1.0,
           SkBlendMode::kSrcOver)));
   return root;
 }
 
 cc::Layer* EffectPaintPropertyNode::ensureDummyLayer() const {
   if (m_dummyLayer)
     return m_dummyLayer.get();
   m_dummyLayer = cc::Layer::Create();
   return m_dummyLayer.get();
 }
 
 String EffectPaintPropertyNode::toString() const {
   return String::format(
       "parent=%p localTransformSpace=%p outputClip=%p opacity=%f filter=%s "
-      "blendMode=%s directCompositingReasons=%s",
+      "blendMode=%s directCompositingReasons=%s compositorElementId=(%d, %d)",
       m_parent.get(), m_localTransformSpace.get(), m_outputClip.get(),
       m_opacity, m_filter.toString().ascii().data(),
       SkBlendMode_Name(m_blendMode),
-      compositingReasonsAsString(m_directCompositingReasons).ascii().data());
+      compositingReasonsAsString(m_directCompositingReasons).ascii().data(),
+      m_compositorElementId.primaryId, m_compositorElementId.secondaryId);
 }
 
 }  // namespace blink