Add terminateServiceWorker method for layout tests - blink side

Source/modules/serviceworkers/testing/InternalsServiceWorker.h

Index: Source/modules/serviceworkers/testing/InternalsServiceWorker.h
diff --git a/Source/modules/serviceworkers/testing/InternalsServiceWorker.h b/Source/modules/serviceworkers/testing/InternalsServiceWorker.h
new file mode 100644
index 0000000000000000000000000000000000000000..248df9371fb4c4af5945217af3cd262bc60804f9
--- /dev/null
+++ b/Source/modules/serviceworkers/testing/InternalsServiceWorker.h
@@ -0,0 +1,20 @@
+// Copyright 2014 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 InternalsServiceWorker_h
+#define InternalsServiceWorker_h
+
+namespace blink {
+
+class Internals;
+class ServiceWorker;
+
+class InternalsServiceWorker {
+public:
+    static void terminateServiceWorker(Internals&, ServiceWorker*);
+};
+
+} // namespace blink
+
+#endif // InternalsServiceWorker_h