I do see two problem in this test case.
1) java/awt/Frame/FrameRepackTest.java does not have yellow horizontal and vertical scrollbars on Mac & Windows . On Mac there is a yellow color is seen at the edge of Vertical & horizontal.
This works as expected in Ubuntu

2) Vertical & horizontal track is not seen in Scrollbar, even though the scrollbar set with ScrollPane.SCROLLBARS_ALWAYS. This is seen only on Mac not on Windows & Ubuntu

Step to reproduce
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1) Run java/awt/Frame/FrameRepackTest.java
2) Click on Flip Menu & Select Visible MenuItem.
3) Observed that scrollbar's Vertical & horizontal tracks is not seen & the scrollbar is not yellow except at the corner of the frame.
If you see then same then the bug is reproduced

This could due to https://bugs.openjdk.org/browse/JDK-8311690