The test imports SunToolkit but doesn't need SunToolkit for anything but realSync, it seems.
Compilation of the test fails with modular build.

We either need to replace realSync with robot.waitForIdle() with JDK9 or grant the usage of sun.awt.
I'm sorry but the first should be right thing to do, event if the test will be different in JDK9 comparing with older releases.