Vibration cannot be canceled during pattern vibration.

Source/modules/testing/InternalsVibration.h

Index: Source/modules/testing/InternalsVibration.h
diff --git a/Source/core/svg/SVGUnknownElement.cpp b/Source/modules/testing/InternalsVibration.h
similarity index 88%
copy from Source/core/svg/SVGUnknownElement.cpp
copy to Source/modules/testing/InternalsVibration.h
index ecc0d2f2f186434ad83a947d92cca241c2bfa3b0..7dbe566120bc6bf96a56c45201de78357338a072 100644
--- a/Source/core/svg/SVGUnknownElement.cpp
+++ b/Source/modules/testing/InternalsVibration.h
@@ -28,14 +28,19 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "config.h"
-#include "core/svg/SVGUnknownElement.h"
+#ifndef InternalsVibration_h
+#define InternalsVibration_h
 
 namespace WebCore {
 
-SVGUnknownElement::SVGUnknownElement(const QualifiedName& tagName, Document* document)
-    : SVGElement(tagName, document)
-{
-}
+class Document;
+class Internals;
+
+class InternalsVibration {
+public:
+    static bool isVibrating(Internals*, Document*);
+};
 
 } // namespace WebCore
+
+#endif // InternalsVibration_h