compositor-worker: Add CompositorProxyClient worker client of CompositorWorker.

third_party/WebKit/Source/core/dom/CompositorProxyClient.h

+// 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.
+
+#ifndef CompositorProxyClient_h
+#define CompositorProxyClient_h
+
+#include "core/CoreExport.h"
+#include "core/workers/WorkerClients.h"
+#include "wtf/Noncopyable.h"
+
+#include <v8.h>
+
+namespace blink {
+
+class CompositorProxy;
+class Event;
+class ScriptState;
+class WorkerClients;
+class WorkerGlobalScope;
+
+class CORE_EXPORT CompositorProxyClient : public Supplement<WorkerClients> {
+    WTF_MAKE_NONCOPYABLE(CompositorProxyClient);
+
+public:
+    CompositorProxyClient() {}
+
+    static CompositorProxyClient* from(WorkerClients*);
+    static const char* supplementName();
+
+    virtual void setGlobalScope(WorkerGlobalScope*) = 0;
+
+    virtual void triggerMutationForTest() = 0;
+};
+
+CORE_EXPORT void provideCompositorProxyClientTo(WorkerClients*, CompositorProxyClient*);
+
+} // namespace blink
+
+#endif // CompositorProxyClient_h