when testing for relaunch in com.sun.deploy.util.JVMParameters.isExcluded() -
special exemption is made when Environment.isJavaWebStart() is true.
(Because AppPolicy.java will add the properties later) but in the case of webstart launching an FX app (or an applet), we switch over to using plugins code (and it's AppPolicy), but leave Environment.isJavaWebStart() true
we should call Environment.setEnvironmentType(Environment.ENV_PLUGIN);
in com.sun.javaws.Launcher.executeApplet() before we switch over to plugin code.