Introduce NavigatorID IDL interface

Source/core/page/NavigatorID.h

Index: Source/core/page/NavigatorID.h
diff --git a/Source/core/svg/SVGUnknownElement.cpp b/Source/core/page/NavigatorID.h
similarity index 81%
copy from Source/core/svg/SVGUnknownElement.cpp
copy to Source/core/page/NavigatorID.h
index ecc0d2f2f186434ad83a947d92cca241c2bfa3b0..c235fe0e422afa2fdef603b8178855cc468b02df 100644
--- a/Source/core/svg/SVGUnknownElement.cpp
+++ b/Source/core/page/NavigatorID.h
@@ -28,14 +28,23 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "config.h"
-#include "core/svg/SVGUnknownElement.h"
+#ifndef NavigatorID_h
+#define NavigatorID_h
+
+#include "wtf/text/WTFString.h"
 
 namespace WebCore {
 
-SVGUnknownElement::SVGUnknownElement(const QualifiedName& tagName, Document* document)
-    : SVGElement(tagName, document)
-{
-}
+class NavigatorBase;
+
+class NavigatorID {
+public:
+    static String appName(const NavigatorBase*);
+    static String appVersion(const NavigatorBase*);
+    static String userAgent(const NavigatorBase*);
+    static String platform(const NavigatorBase*);
+};
 
 } // namespace WebCore
+
+#endif // NavigatorID_h