compositor-worker: Introduce CompositorWorker.

Source/modules/compositorworker/CompositorWorkerThread.h

+// Copyright 2015 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.
+
+#ifndef CompositorWorkerThread_h
+#define CompositorWorkerThread_h
+
+#include "core/workers/DedicatedWorkerThread.h"
+
+namespace blink {
+
+class CompositorWorkerThread final : public DedicatedWorkerThread {

[kinuko, 2015/03/25 05:48:45]

If we're going to use the underlying thread differently from the existing
dedicated worker, I think it's cleaner to make this class just inherit from
WorkerThread but not from DedicatedWorkerThread. (It looks not much code is
resused in the new class either)

[sadrul, 2015/03/25 06:13:07]

WorkerMessagingProxy::createWorkerThread() expects a DedicatedWorkerThread to be
returned. So unfortunately this needs to be a DedicatedWorkerThread (for now).

[tkent, 2015/03/25 07:37:55]

Probably we should introduce new WorkerThread class which is a base class of
DedicatedWorkerThread and CompositorWorkerThread.

[sadrul, 2015/03/26 01:27:48]

Turns out, we can just use 'WorkerThread' (instead of DedicatedWorkerThread).
Done.

+public:
+    static PassRefPtr<CompositorWorkerThread> create(PassRefPtr<WorkerLoaderProxy>, WorkerObjectProxy&, double timeOrigin, PassOwnPtrWillBeRawPtr<WorkerThreadStartupData>);
+    virtual ~CompositorWorkerThread();
+
+private:
+    CompositorWorkerThread(PassRefPtr<WorkerLoaderProxy>, WorkerObjectProxy&, double timeOrigin, PassOwnPtrWillBeRawPtr<WorkerThreadStartupData>);
+
+    v8::Isolate* initializeIsolate() override;
+    void willDestroyIsolate() override;
+    void destroyIsolate() override;
+    void terminateV8Execution() override;
+
+    PassOwnPtr<WebThreadSupportingGC> createWebThreadSupportingGC() override;
+    void didStartRunLoop() override;
+    void didStopRunLoop() override;
+};
+
+} // namespace blink
+
+#endif // CompositorWorkerThread_h