To reproduce this bug, run the regression test located at
test/java/awt/Focus/WindowTest. Focus any Component in the Window and hold down
CTRL-TAB. Focus will begin cycling through all of the Components, wrapping back
to the first Component after completing a cycle. Now, while still holding down
CTRL-TAB, move the mouse cursor the owning Frame and start clicking on the Frame
with a mouse button. After several clicks, focus will stop traversing though
the Window.

This behavior is not desirable, because there are no Components in the owning
Frame which should steal focus or otherwise impede the ongoing traversal. This
bug is not reproducible on Windows.