Refactor BackingThreadHolder to WorkletBackingThreadHolder

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

Index: third_party/WebKit/Source/core/workers/WorkletBackingThreadHolder.h
diff --git a/third_party/WebKit/Source/core/workers/WorkletBackingThreadHolder.h b/third_party/WebKit/Source/core/workers/WorkletBackingThreadHolder.h
new file mode 100644
index 0000000000000000000000000000000000000000..2f47c61734dda64b74139cabff3bdf08246560a3
--- /dev/null
+++ b/third_party/WebKit/Source/core/workers/WorkletBackingThreadHolder.h
@@ -0,0 +1,32 @@
+// 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 WorkletBackingThreadHolder_h
+#define WorkletBackingThreadHolder_h
+
+#include "core/CoreExport.h"
+#include "wtf/PtrUtil.h"
+
+namespace blink {
+
+class WorkerBackingThread;
+class WaitableEvent;
+
+class CORE_EXPORT WorkletBackingThreadHolder {
+ public:
+  WorkerBackingThread* thread() { return m_thread.get(); }
+
+ protected:
+  explicit WorkletBackingThreadHolder(std::unique_ptr<WorkerBackingThread>);
+  virtual void initializeOnThread() = 0;
+  void shutdownAndWait();
+  void shutdownOnThread(WaitableEvent*);
+
+  std::unique_ptr<WorkerBackingThread> m_thread;
+  bool m_initialized;
+};
+
+}  // namespace blink
+
+#endif  // WorkletBackingThreadHolder_h