All these tests fail similarly on Ubuntu 16.04
java/awt/Modal/ToBack/ToBackAppModal1Test.java: Check whether an application modal dialog having a null Frame constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackAppModal2Test.java: Check whether an application modal dialog having a null Dialog constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackAppModal3Test.java: Check whether an application modal dialog having a hidden Frame constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackAppModal4Test.java: Check whether an application modal dialog having a hidden Dialog constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackModal1Test.java: Check whether a modal dialog having a null Frame constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackModal2Test.java: Check whether a modal dialog having a null Dialog constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackModal3Test.java: Check whether a modal dialog having a hidden Frame constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackModal4Test.java: Check whether a modal dialog having a hidden Dialog constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackTKModal1Test.java: Check whether a toolkit modal dialog having a null Frame constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackTKModal2Test.java: Check whether a toolkit modal dialog having a null Dialog constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackTKModal3Test.java: Check whether a toolkit modal dialog having a hidden Frame constructor still stays on top of the blocked windows even after calling toBack for the dialog.
java/awt/Modal/ToBack/ToBackTKModal4Test.java

java.lang.reflect.InvocationTargetException
at java.desktop/java.awt.EventQueue.invokeAndWait(EventQueue.java:1367)
at java.desktop/java.awt.EventQueue.invokeAndWait(EventQueue.java:1342)
at ToBackFDFTest.Test(ToBackFDFTest.java:167)
at ToBackFDFTest.doTest(ToBackFDFTest.java:256)
at ToBackAppModal2Test.main(ToBackAppModal2Test.java:46)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:115)
at java.base/java.lang.Thread.run(Thread.java:844)
Caused by: java.lang.RuntimeException: Calling toBack for the blocked frame pushed the blocking dialog to back.: expected false to equal true