Implementation of setSinkId() for HTMLMediaElement.

Source/modules/audio_output_devices/SetSinkIdCallbacks.h

Index: Source/modules/audio_output_devices/SetSinkIdCallbacks.h
diff --git a/Source/modules/audio_output_devices/SetSinkIdCallbacks.h b/Source/modules/audio_output_devices/SetSinkIdCallbacks.h
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+++ b/Source/modules/audio_output_devices/SetSinkIdCallbacks.h
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+// 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 SetSinkIdCallbacks_h
+#define SetSinkIdCallbacks_h
+
+#include "platform/Timer.h"
+#include "platform/heap/Handle.h"
+#include "public/platform/WebCallbacks.h"
+#include "wtf/Noncopyable.h"
+#include "wtf/PassRefPtr.h"
+#include "wtf/RefPtr.h"
+
+namespace blink {
+
+class HTMLMediaElement;
+class ScriptPromiseResolver;
+struct WebSetSinkIdError;
+
+class SetSinkIdCallbacks final : public WebCallbacks<void, WebSetSinkIdError> {
+    WTF_MAKE_NONCOPYABLE(SetSinkIdCallbacks);
+public:
+    SetSinkIdCallbacks(PassRefPtrWillBeRawPtr<ScriptPromiseResolver>, HTMLMediaElement&, const String& sinkId);
+    ~SetSinkIdCallbacks() override;
+
+    void onSuccess() override;
+    void onError(WebSetSinkIdError*) override;
+
+private:
+    RefPtrWillBePersistent<ScriptPromiseResolver> m_resolver;
+    RefPtrWillBePersistent<HTMLMediaElement> m_element;
+    String m_sinkId;
+};
+
+} // namespace blink
+
+#endif // SetSinkIdCallbacks_h