[worklets] Introduce ThreadedWorkletMessagingProxy and AnimationWorkletMessagaingProxy.

third_party/WebKit/Source/core/workers/ThreadedWorkletMessagingProxy.h

Index: third_party/WebKit/Source/core/workers/ThreadedWorkletMessagingProxy.h
diff --git a/third_party/WebKit/Source/core/workers/ThreadedWorkletMessagingProxy.h b/third_party/WebKit/Source/core/workers/ThreadedWorkletMessagingProxy.h
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index 0000000000000000000000000000000000000000..a111c275d6a971df807f013c8f63e9448a903495
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+++ b/third_party/WebKit/Source/core/workers/ThreadedWorkletMessagingProxy.h
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+// 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 ThreadedWorkletMessagingProxy_h
+#define ThreadedWorkletMessagingProxy_h
+
+#include "core/CoreExport.h"
+#include "core/workers/ThreadedMessagingProxyBase.h"
+#include "core/workers/WorkletGlobalScopeProxy.h"
+
+namespace blink {
+
+class ThreadedWorkletObjectProxy;
+
+class CORE_EXPORT ThreadedWorkletMessagingProxy
+    : public ThreadedMessagingProxyBase
+    , public WorkletGlobalScopeProxy {
+public:
+    // WorkletGlobalScopeProxy implementation.
+    void evaluateScript(const ScriptSourceCode&) final;
+    void terminateWorkletGlobalScope() final;
+
+    void initialize();
+
+protected:
+    explicit ThreadedWorkletMessagingProxy(ExecutionContext*);
+
+    ThreadedWorkletObjectProxy& workletObjectProxy() { return *m_workletObjectProxy; }
+
+private:
+    std::unique_ptr<ThreadedWorkletObjectProxy> m_workletObjectProxy;
+};
+
+} // namespace blink
+
+#endif // ThreadedWorkletMessagingProxy_h