Removing unneeded imports from testcode

[Robert Lichtenberger]

I'm in the process of preparing a fix for JDK-8236912 and I (or rather
eclipse) have noticed that WebViewTest contains an import of
java.util.concurrent.FutureTask that is not needed.
What is the correct way of handling such things:
* Including them into the Pull-Request for the fix of JDK-8236912
* Leaving the unneeded import as-is.
* Opening another issue
Best regards,
Robert