[worklets] Split apart CompositorWorkerThread for sharing with AnimationWorkletThread.

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

+// Copyright 2016 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/AnimationWorkletThread.h"
+
+#include "core/workers/WorkerThreadStartupData.h"
+#include "platform/TraceEvent.h"
+#include "wtf/PtrUtil.h"
+
+namespace blink {
+
+std::unique_ptr<AnimationWorkletThread> AnimationWorkletThread::create(PassRefPtr<WorkerLoaderProxy> workerLoaderProxy, WorkerReportingProxy& workerReportingProxy)
+{
+    TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("animation-worklet"), "AnimationWorkletThread::create");
+    DCHECK(isMainThread());
+    return wrapUnique(new AnimationWorkletThread(workerLoaderProxy, workerReportingProxy));
+}
+
+AnimationWorkletThread::AnimationWorkletThread(PassRefPtr<WorkerLoaderProxy> workerLoaderProxy, WorkerReportingProxy& workerReportingProxy)
+    : AbstractAnimationWorkletThread(workerLoaderProxy, workerReportingProxy)
+{
+}
+
+AnimationWorkletThread::~AnimationWorkletThread()
+{
+}
+
+WorkerOrWorkletGlobalScope* AnimationWorkletThread::createWorkerGlobalScope(std::unique_ptr<WorkerThreadStartupData> startupData)
+{
+    TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("animation-worklet"), "AnimationWorkletThread::createWorkerGlobalScope");
+    // TODO(ikilpatrick): implement.
+    return nullptr;
+}
+
+} // namespace blink