CC Animation: Use ElementId to attach CC animation players.

third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp

Index: third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
diff --git a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
index 9daccaf0230176950c136827b4cd06c43b25b49a..6d3121bd6a75db04bc750c64f870f330007f6bba 100644
--- a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
+++ b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
@@ -555,7 +555,8 @@ bool CompositedLayerMapping::updateGraphicsLayerConfiguration()
     if (layerConfigChanged || maskLayerChanged)
         updatePaintingPhases();
 
-    updateElementIdAndCompositorMutableProperties();
+    updateCompositorElementId();
+    updateCompositorMutableProperties();
 
     return layerConfigChanged;
 }
@@ -741,7 +742,8 @@ void CompositedLayerMapping::updateGraphicsLayerGeometry(const PaintLayer* compo
     updateContentsRect();
     updateBackgroundColor();
     updateDrawsContent();
-    updateElementIdAndCompositorMutableProperties();
+    updateCompositorElementId();
+    updateCompositorMutableProperties();
     updateContentsOpaque();
     updateAfterPartResize();
     updateRenderingContext();
@@ -1488,14 +1490,32 @@ void CompositedLayerMapping::updateShouldFlattenTransform()
     }
 }
 
-void CompositedLayerMapping::updateElementIdAndCompositorMutableProperties()
+void CompositedLayerMapping::updateCompositorElementId()
+{
+    if (Node* owningNode = m_owningLayer.layoutObject()->generatingNode()) {

[esprehn, 2016/05/10 22:55:13]

we can just keep a data member on CompositedLayerMapping for this, CLM must
exist if anything in cc exists, and if CLM is destroyed anything in cc must be
destroyed too.

If the question is about CompositorWorker then we should use DOMNodeIds.

[loyso (OOO), 2016/05/12 06:02:15]

Do you mean
Node* CompositedLayerMapping::m_owningNode 
or
CompositorElementId CompositedLayerMapping::m_compositorElementId (a unique for
CompositedLayerMapping, 1 per CLM)
?

+        if (owningNode->isElementNode()) {
+            Element* owningElement = toElement(owningNode);
+            if (owningElement->layoutObject() == m_owningLayer.layoutObject()) {
+                CompositorElementId elementId = owningElement->compositorElementId();
+                if (m_scrollingContentsLayer.get()) {
+                    // Any scrolling layer may attract compositor-initiated
+                    // animation, so assign an id in advance.
+                    elementId = owningElement->assignCompositorElementId();
+                    m_scrollingContentsLayer->setElementId(elementId);
+                }
+                m_graphicsLayer->setElementId(elementId);
+            }
+        }
+    }
+}
+
+void CompositedLayerMapping::updateCompositorMutableProperties()
 {
     if (!RuntimeEnabledFeatures::compositorWorkerEnabled())
         return;
 
     TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("compositor-worker"), "CompositedLayerMapping::updateElementId()");
 
-    CompositorElementId elementId = 0;
     uint32_t mainMutableProperties = CompositorMutableProperty::kNone;
     uint32_t scrollMutableProperties = CompositorMutableProperty::kNone;
 
@@ -1503,22 +1523,23 @@ void CompositedLayerMapping::updateElementIdAndCompositorMutableProperties()
         if (Node* owningNode = m_owningLayer.layoutObject()->generatingNode()) {
             if (owningNode->isElementNode()) {
                 Element* owningElement = toElement(owningNode);
-                uint32_t compositorMutableProperties = owningElement->compositorMutableProperties();
-                elementId = owningElement->assignCompositorElementId();
+
+                const CompositorElementId elementId = owningElement->assignCompositorElementId();
                 CompositorIdToElementMap::registerElement(*owningElement);
+                m_graphicsLayer->setElementId(elementId);
+                if (m_scrollingContentsLayer.get())
+                    m_scrollingContentsLayer->setElementId(elementId);
+
+                uint32_t compositorMutableProperties = owningElement->compositorMutableProperties();
                 mainMutableProperties = (CompositorMutableProperty::kOpacity | CompositorMutableProperty::kTransform) & compositorMutableProperties;
                 scrollMutableProperties = (CompositorMutableProperty::kScrollLeft | CompositorMutableProperty::kScrollTop) & compositorMutableProperties;
             }
         }
     }
 
-    m_graphicsLayer->setElementId(elementId);
     m_graphicsLayer->setCompositorMutableProperties(mainMutableProperties);
-
-    if (m_scrollingContentsLayer.get()) {
-        m_scrollingContentsLayer->setElementId(elementId);
+    if (m_scrollingContentsLayer.get())
         m_scrollingContentsLayer->setCompositorMutableProperties(scrollMutableProperties);
-    }
 }
 
 bool CompositedLayerMapping::updateForegroundLayer(bool needsForegroundLayer)