Introduce WebMediaSession

third_party/WebKit/public/platform/modules/mediasession/WebMediaSessionError.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 WebMediaSessionError_h
+#define WebMediaSessionError_h
+
+namespace blink {
+
+struct WebMediaSessionError {
+    enum ErrorType {
+        ErrorTypeActivate = 0,
+        ErrorTypeLast = ErrorTypeActivate
+    };
+
+    WebMediaSessionError(ErrorType errorType)
+        : errorType(errorType)
+    {
+    }
+
+    ErrorType errorType;
+};
+
+} // namespace blink
+
+#endif // WebMediaSessionError_h