cc : Delete LayerImpl::OnOpacityAnimated

cc/input/scrollbar_animation_controller_thinning.cc

Index: cc/input/scrollbar_animation_controller_thinning.cc
diff --git a/cc/input/scrollbar_animation_controller_thinning.cc b/cc/input/scrollbar_animation_controller_thinning.cc
index 1a124ddf05093f27f89e5506272a5f7449fed89d..af02ad3cddb6d2ebf5b31d877bcecdba8abd8ac1 100644
--- a/cc/input/scrollbar_animation_controller_thinning.cc
+++ b/cc/input/scrollbar_animation_controller_thinning.cc
@@ -143,7 +143,20 @@ void ScrollbarAnimationControllerThinning::ApplyOpacityAndThumbThicknessScale(
             ? AdjustScale(opacity, scrollbar->Opacity(), opacity_change_)
             : 0;
 
-    scrollbar->OnOpacityAnimated(effective_opacity);
+    PropertyTrees* property_trees =
+        scrollbar->layer_tree_impl()->property_trees();
+    // If this method is called during LayerImpl::PushPropertiesTo, we may not
+    // yet have valid effect_id_to_index_map entries as property trees are
+    // pushed after layers during activation. We can skip updating opacity in
+    // that case as we are only registering a scrollbar and because opacity will
+    // be overwritten anyway when property trees are pushed.
+    if (property_trees->IsInIdToIndexMap(PropertyTrees::TreeType::EFFECT,
+                                         scrollbar->id())) {
+      property_trees->effect_tree.OnOpacityAnimated(
+          effective_opacity,
+          property_trees->effect_id_to_index_map[scrollbar->id()],
+          scrollbar->layer_tree_impl());
+    }
     scrollbar->SetThumbThicknessScaleFactor(AdjustScale(
         thumb_thickness_scale, scrollbar->thumb_thickness_scale_factor(),
         thickness_change_));