cc : Track opacity animation changes on effect tree

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 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/layer_tree_host_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 3920 matching lines @@
     ElementListType list_type,
     bool is_animating) {
   if (list_type == ElementListType::ACTIVE) {
     TreeLayerTransformIsPotentiallyAnimatingChanged(element_id, active_tree(),
                                                     is_animating);
   } else {
     TreeLayerTransformIsPotentiallyAnimatingChanged(element_id, pending_tree(),
                                                     is_animating);
   }
 }
+void LayerTreeHostImpl::ElementOpacityIsAnimatingChanged(
+    ElementId element_id,
+    ElementListType list_type,
+    AnimationChangeType change_type,
+    bool is_animating) {
+  LayerTreeImpl* tree =
+      list_type == ElementListType::ACTIVE ? active_tree() : pending_tree();
+  if (!tree)
+    return;
+  LayerImpl* layer = tree->LayerById(element_id);
+  if (layer) {
+    switch (change_type) {
+      case AnimationChangeType::POTENTIAL:
+        layer->OnOpacityIsPotentiallyAnimatingChanged(is_animating);
+        break;
+      case AnimationChangeType::RUNNING:
+        layer->OnOpacityIsCurrentlyAnimatingChanged(is_animating);
+        break;
+      case AnimationChangeType::BOTH:
+        layer->OnOpacityIsPotentiallyAnimatingChanged(is_animating);
+        layer->OnOpacityIsCurrentlyAnimatingChanged(is_animating);
+        break;
+    }
+  }
+}
 
 void LayerTreeHostImpl::ScrollOffsetAnimationFinished() {
   // TODO(majidvp): We should pass in the original starting scroll position here
   ScrollStateData scroll_state_data;
   ScrollState scroll_state(scroll_state_data);
   ScrollEnd(&scroll_state);
 }
 
 gfx::ScrollOffset LayerTreeHostImpl::GetScrollOffsetForAnimation(
     ElementId element_id) const {
@@ skipping 11 matching lines @@
   return task_runner_provider_->HasImplThread();
 }
 
 bool LayerTreeHostImpl::CommitToActiveTree() const {
   // In single threaded mode we skip the pending tree and commit directly to the
   // active tree.
   return !task_runner_provider_->HasImplThread();
 }
 
 }  // namespace cc