Sun Yaqi reported the issue:

configure --with-import-modules=modular-sdk

make run-test CONF=fastdebug TEST="tools/launcher/FXLauncherTest.java" failed:

`
----------System.err:(11/697)----------
java.lang.RuntimeException: JavaFX modules erroneously included in the JDK
    at FXLauncherTest.main(FXLauncherTest.java:451)
    at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
    at java.base/java.lang.reflect.Method.invoke(Method.java:578)
    at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
    at java.base/java.lang.Thread.run(Thread.java:1589)

JavaTest Message: Test threw exception: java.lang.RuntimeException: JavaFX modules erroneously included in the JDK
JavaTest Message: shutting down test

STATUS:Failed.`main' threw exception: java.lang.RuntimeException: JavaFX modules erroneously included in the JDK
`