The new unit tests added for RT-20295 cause the JVM running the unit tests to fail with too many open files. Once this happens, all subsequent tests in the graphics module fail (several hundred of them).

The failures are of the following form.

com.sun.javafx.iio.GIFLoaderTest > testReadGIFFile FAILED
    javax.imageio.IIOException: Can't create cache file!
        at javax.imageio.ImageIO.createImageInputStream(ImageIO.java:361)
        at javax.imageio.ImageIO.read(ImageIO.java:1351)
        at com.sun.javafx.iio.GIFLoaderTest.testReadGIFFile(GIFLoaderTest.java:217)
        at com.sun.javafx.iio.GIFLoaderTest.testReadGIFFile(GIFLoaderTest.java:226)

        Caused by:
        java.nio.file.FileSystemException: /tmp/imageio3789392384406929084.tmp: Too many open files


OR:

com.sun.javafx.geom.TransformedShapeTest > initializationError FAILED
    java.lang.ClassNotFoundException: com.sun.javafx.geom.TransformedShapeTest

        Caused by:
        java.io.FileNotFoundException: /localhome/kcr/javafx/8u-kcr/jfx/rt/modules/graphics/build/classes/test/com/sun/javafx/geom/TransformedShapeTest.class (Too many open files)