CC Animation: Use ElementId to attach CC animation players.

third_party/WebKit/Source/platform/scroll/ScrollAnimatorCompositorCoordinator.cpp

Index: third_party/WebKit/Source/platform/scroll/ScrollAnimatorCompositorCoordinator.cpp
diff --git a/third_party/WebKit/Source/platform/scroll/ScrollAnimatorCompositorCoordinator.cpp b/third_party/WebKit/Source/platform/scroll/ScrollAnimatorCompositorCoordinator.cpp
index 5dcc838fcfe1c0a0e10bc00ad189a783e977f59e..3d41d128b5841ed4ce633e29d53cc4fc53eb34b5 100644
--- a/third_party/WebKit/Source/platform/scroll/ScrollAnimatorCompositorCoordinator.cpp
+++ b/third_party/WebKit/Source/platform/scroll/ScrollAnimatorCompositorCoordinator.cpp
@@ -17,7 +17,7 @@
 namespace blink {
 
 ScrollAnimatorCompositorCoordinator::ScrollAnimatorCompositorCoordinator()
-    : m_compositorAnimationAttachedToLayerId(0)
+    : m_compositorAnimationAttachedToElementId(0)
     , m_runState(RunState::Idle)
     , m_compositorAnimationId(0)
     , m_compositorAnimationGroupId(0)
@@ -66,7 +66,7 @@ bool ScrollAnimatorCompositorCoordinator::hasAnimationThatRequiresService() cons
 bool ScrollAnimatorCompositorCoordinator::addAnimation(
     PassOwnPtr<CompositorAnimation> animation)
 {
-    if (m_compositorPlayer->isLayerAttached()) {
+    if (m_compositorPlayer->isElementAttached()) {
         m_compositorPlayer->addAnimation(animation.leakPtr());
         return true;
     }
@@ -75,13 +75,13 @@ bool ScrollAnimatorCompositorCoordinator::addAnimation(
 
 void ScrollAnimatorCompositorCoordinator::removeAnimation()
 {
-    if (m_compositorPlayer->isLayerAttached())
+    if (m_compositorPlayer->isElementAttached())
         m_compositorPlayer->removeAnimation(m_compositorAnimationId);
 }
 
 void ScrollAnimatorCompositorCoordinator::abortAnimation()
 {
-    if (m_compositorPlayer->isLayerAttached())
+    if (m_compositorPlayer->isElementAttached())
         m_compositorPlayer->abortAnimation(m_compositorAnimationId);
 }
 
@@ -171,27 +171,30 @@ bool ScrollAnimatorCompositorCoordinator::reattachCompositorPlayerIfNeeded(
     CompositorAnimationTimeline* timeline)
 {
     bool reattached = false;
-    int compositorAnimationAttachedToLayerId = 0;
-    if (getScrollableArea()->layerForScrolling())
-        compositorAnimationAttachedToLayerId = getScrollableArea()->layerForScrolling()->platformLayer()->id();
+    CompositorElementId compositorAnimationAttachedToElementId = 0;
+    GraphicsLayer* layerForScrolling = getScrollableArea()->layerForScrolling();
+    if (layerForScrolling) {
+        if (!layerForScrolling->platformLayer()->elementId())
+            layerForScrolling->platformLayer()->setElementId(nextCompositorElementId());
+        compositorAnimationAttachedToElementId = layerForScrolling->platformLayer()->elementId();
+    }
 
-    if (compositorAnimationAttachedToLayerId != m_compositorAnimationAttachedToLayerId) {
+    if (compositorAnimationAttachedToElementId != m_compositorAnimationAttachedToElementId) {
         if (m_compositorPlayer && timeline) {
             // Detach from old layer (if any).
-            if (m_compositorAnimationAttachedToLayerId) {
-                if (m_compositorPlayer->isLayerAttached())
-                    m_compositorPlayer->detachLayer();
+            if (m_compositorAnimationAttachedToElementId) {
+                if (m_compositorPlayer->isElementAttached())
+                    m_compositorPlayer->detachElement();
                 timeline->playerDestroyed(*this);
             }
             // Attach to new layer (if any).
-            if (compositorAnimationAttachedToLayerId) {
-                ASSERT(!m_compositorPlayer->isLayerAttached());
+            if (compositorAnimationAttachedToElementId) {
+                ASSERT(!m_compositorPlayer->isElementAttached());
                 timeline->playerAttached(*this);
-                m_compositorPlayer->attachLayer(
-                    getScrollableArea()->layerForScrolling()->platformLayer());
+                m_compositorPlayer->attachElement(compositorAnimationAttachedToElementId);
                 reattached = true;
             }
-            m_compositorAnimationAttachedToLayerId = compositorAnimationAttachedToLayerId;
+            m_compositorAnimationAttachedToElementId = compositorAnimationAttachedToElementId;
         }
     }