Remove owning_id from EffectNode and replace it by an opaque stable_id

cc/trees/property_tree.cc

Index: cc/trees/property_tree.cc
diff --git a/cc/trees/property_tree.cc b/cc/trees/property_tree.cc
index fbedc16878b0cfe83a49df79688311b9513bdcab..75f76bce83a6b97ad01116fc62b7712ceae6262a 100644
--- a/cc/trees/property_tree.cc
+++ b/cc/trees/property_tree.cc
@@ -760,6 +760,12 @@ EffectTree::EffectTree() {
 
 EffectTree::~EffectTree() {}
 
+#if DCHECK_IS_ON()
+bool EffectTree::LookupByOnwningLayerIdAllowed() const {
+  return false;
+}
+#endif
+
 int EffectTree::Insert(const EffectNode& tree_node, int parent_id) {
   int node_id = PropertyTree<EffectNode>::Insert(tree_node, parent_id);
   DCHECK_EQ(node_id, static_cast<int>(render_surfaces_.size()));
@@ -1014,7 +1020,7 @@ void EffectTree::UpdateRenderSurfaces(LayerTreeImpl* layer_tree_impl) {
 
     if (needs_render_surface) {
       render_surfaces_[id] = base::MakeUnique<RenderSurfaceImpl>(
-          layer_tree_impl, effect_node->owning_layer_id);
+          layer_tree_impl, effect_node->stable_id);
       render_surfaces_[id]->set_effect_tree_index(id);
     } else {
       render_surfaces_[id].reset();
@@ -1059,7 +1065,7 @@ bool EffectTree::CreateOrReuseRenderSurfaces(
     EffectNode* node = Node(id);
     if (node->has_render_surface) {
       stable_id_node_id_list.push_back(
-          std::make_pair(node->owning_layer_id, node->id));
+          std::make_pair(node->stable_id, node->id));
     }
   }
 
@@ -1718,11 +1724,12 @@ void PropertyTrees::SetInnerViewportScrollBoundsDelta(
 }
 
 void PropertyTrees::PushOpacityIfNeeded(PropertyTrees* target_tree) {
-  for (int id : target_tree->always_use_active_tree_opacity_effect_ids) {
+  for (const ElementId& element_id :
+       target_tree->always_use_active_tree_opacity_effect_ids) {
     if (const EffectNode* source_effect_node =
-            effect_tree.FindNodeFromOwningLayerId(id)) {
+            effect_tree.FindNodeFromElementId(element_id)) {
       EffectNode* target_effect_node =
-          target_tree->effect_tree.UpdateNodeFromOwningLayerId(id);
+          target_tree->effect_tree.FindNodeFromElementId(element_id);
       float source_opacity = source_effect_node->opacity;
       float target_opacity = target_effect_node->opacity;
       if (source_opacity == target_opacity)
@@ -1737,7 +1744,6 @@ void PropertyTrees::RemoveIdFromIdToIndexMaps(int id) {
   transform_tree.SetOwningLayerIdForNode(nullptr, id);
   clip_tree.SetOwningLayerIdForNode(nullptr, id);
   scroll_tree.SetOwningLayerIdForNode(nullptr, id);
-  effect_tree.SetOwningLayerIdForNode(nullptr, id);
 }
 
 void PropertyTrees::UpdateChangeTracking() {