Platform.isSupported(MEDIA|WEB) passes when it should not on embedded

This is because there is a simple reflection test for MediaView and WebView, and the classes are present even though there is no native support present.

SE Embedded jars (jfxrt-graphics...) have these classes filtered.
SE for ARM (jfxrt.jar) does not have them filtered - which can affect some tests, particularly developer tests.

Perhaps we could/should change the isSupported test for ARM until we more fully support these feaures (currently we have a flag to enable 3D).