Remove owning_id from EffectNode and replace it by an opaque stable_id

cc/trees/property_tree_builder.cc

 // 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 "cc/trees/property_tree_builder.h"
 
 #include <stddef.h>
 
 #include <map>
 #include <set>
@@ skipping 899 matching lines @@
     data_for_children->effect_tree_parent = parent_id;
     data_for_children->compound_transform_since_render_target *=
         Transform(layer);
     return false;
   }
 
   EffectTree& effect_tree = data_for_children->property_trees->effect_tree;
   int node_id = effect_tree.Insert(EffectNode(), parent_id);
   EffectNode* node = effect_tree.back();
 
-  node->owning_layer_id = layer->id();
+  node->stable_id = layer->id();
   if (AlwaysUseActiveTreeOpacity(layer)) {
+    DCHECK(layer->element_id());
     data_for_children->property_trees->always_use_active_tree_opacity_effect_ids
-        .push_back(node->owning_layer_id);
+        .push_back(layer->element_id());
   }
 
   node->opacity = Opacity(layer);
   node->blend_mode = BlendMode(layer);
   node->unscaled_mask_target_size = layer->bounds();
   node->has_render_surface = should_create_render_surface;
   node->has_copy_request = HasCopyRequest(layer);
   node->filters = Filters(layer);
   node->background_filters = BackgroundFilters(layer);
   node->filters_origin = FiltersOrigin(layer);
@@ skipping 33 matching lines @@
     // factor) and clip node created from root layer (include viewports) applies
     // to root render surface's content, but not root render surface itself.
     node->transform_id = TransformTree::kRootNodeId;
     node->clip_id = ClipTree::kViewportNodeId;
   }
 
   data_for_children->closest_ancestor_with_copy_request =
       node->closest_ancestor_with_copy_request_id;
   data_for_children->effect_tree_parent = node_id;
   layer->SetEffectTreeIndex(node_id);
-  data_for_children->property_trees->effect_tree.SetOwningLayerIdForNode(
-      effect_tree.back(), layer->id());
 
   // For animation subsystem purposes, if this layer has a compositor element
   // id, we build a map from that id to this effect node.
   if (layer->element_id()) {
     data_for_children->property_trees
         ->element_id_to_effect_node_index[layer->element_id()] = node_id;
   }
 
   std::vector<std::unique_ptr<CopyOutputRequest>> layer_copy_requests;
   TakeCopyRequests(layer, &layer_copy_requests);
@@ skipping 403 matching lines @@
       root_layer, page_scale_layer, inner_viewport_scroll_layer,
       outer_viewport_scroll_layer, overscroll_elasticity_layer,
       elastic_overscroll, page_scale_factor, device_scale_factor, viewport,
       device_transform, property_trees, color);
   property_trees->effect_tree.CreateOrReuseRenderSurfaces(
       &render_surfaces, root_layer->layer_tree_impl());
   property_trees->ResetCachedData();
 }
 
 }  // namespace cc