[PresentationAPI] Added plumbing for start/joinSession from JS to platform

Source/modules/presentation/PresentationError.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 PresentationError_h
+#define PresentationError_h
+
+#include "platform/heap/Handle.h"
+#include "public/platform/modules/presentation/WebPresentationError.h"
+
+namespace blink {
+
+class DOMException;
+
+// A container of methods taking care of WebPresentationError in WebCallbacks subclasses.
+class PresentationError final {
+public:
+    static PassRefPtrWillBeRawPtr<DOMException> take(WebPresentationError*);
+    static void dispose(WebPresentationError*);
+
+private:
+    ~PresentationError() = delete;
+};
+
+} // namespace blink
+
+#endif // PresentationError_h