Add UseCounters for ViewportAPI

third_party/WebKit/Source/core/events/VisualViewportResizeEvent.h

Index: third_party/WebKit/Source/core/events/VisualViewportResizeEvent.h
diff --git a/third_party/WebKit/Source/core/events/VisualViewportResizeEvent.h b/third_party/WebKit/Source/core/events/VisualViewportResizeEvent.h
new file mode 100644
index 0000000000000000000000000000000000000000..26e578a0d74b3b6729235f2844689e8f2273f03d
--- /dev/null
+++ b/third_party/WebKit/Source/core/events/VisualViewportResizeEvent.h
@@ -0,0 +1,31 @@
+// Copyright 2016 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 VisualViewportResizeEvent_h
+#define VisualViewportResizeEvent_h
+
+#include "core/events/Event.h"
+
+namespace blink {
+
+class VisualViewportResizeEvent final : public Event {
+public:
+    ~VisualViewportResizeEvent() override;
+
+    static VisualViewportResizeEvent* create()
+    {
+        return new VisualViewportResizeEvent();
+    }
+
+    void doneDispatchingEventAtCurrentTarget() override;
+
+    DEFINE_INLINE_VIRTUAL_TRACE() { Event::trace(visitor); }
+
+private:
+    VisualViewportResizeEvent();
+};
+
+} // namespace blink
+
+#endif // VisualViewportResizeEvent_h