Test bug fix review request.

[Andrey Rusakov]

Hi everyone.
Please take a look at my fix for openjfx tests: JDK-8159962 
<https://bugs.openjdk.java.net/browse/JDK-8159962> (webrev 
<http://cr.openjdk.java.net/%7Earusakov/8159962/webrev.00/>) and 
JDK-8160065 <https://bugs.openjdk.java.net/browse/JDK-8160065> (webrev 
<http://cr.openjdk.java.net/%7Earusakov/8160065/webrev.00/>)
Fixes are applicable for both 8 and 9 tests.