Use wrapper tracing for worklets.

third_party/WebKit/Source/modules/compositorworker/AnimatorDefinition.cpp

 // Copyright 2017 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 "modules/compositorworker/AnimatorDefinition.h"
 
 #include "core/dom/ExecutionContext.h"
 #include "modules/compositorworker/Animator.h"
 #include "platform/bindings/ScriptState.h"
 #include "platform/bindings/V8Binding.h"
 #include "platform/bindings/V8ObjectConstructor.h"
 
 namespace blink {
 
 AnimatorDefinition::AnimatorDefinition(v8::Isolate* isolate,
                                        v8::Local<v8::Function> constructor,
                                        v8::Local<v8::Function> animate)
-    : constructor_(isolate, constructor), animate_(isolate, animate) {}
+    : constructor_(isolate, this, constructor),
+      animate_(isolate, this, animate) {}
 
 AnimatorDefinition::~AnimatorDefinition() {}
 
+DEFINE_TRACE_WRAPPERS(AnimatorDefinition) {
+  visitor->TraceWrappers(constructor_.Cast<v8::Value>());
+  visitor->TraceWrappers(animate_.Cast<v8::Value>());
+}
+
 v8::Local<v8::Function> AnimatorDefinition::ConstructorLocal(
     v8::Isolate* isolate) {
   return constructor_.NewLocal(isolate);
 }
 
 }  // namespace blink