[11u] RFR: JDK-8247753: UIManager.getSytemLookAndFeelClassName() returns wrong value on Fedora 32

[Ramanand Patil]

Hi all,
Please review the JDK11u backport of JDK-8247753: UIManager.getSytemLookAndFeelClassName() returns wrong value on Fedora 32
Bug Link: https://bugs.openjdk.java.net/browse/JDK-8247753
Webrev: http://cr.openjdk.java.net/~rpatil/8247753/webrev.00/
JDK-16 Changeset: https://hg.openjdk.java.net/jdk/jdk/rev/97a5fd3612ef
The patch was not applied cleanly from JDK16 to JDK11u as the check for the environmental variables "GNOME_DESKTOP_SESSION_ID" and "XDG_CURRENT_DESKTOP" is done in native code (unix/native/libjava/java_props_md.c) in jdk11u.
The test case is taken from the latest jdk repo by ignoring the changes done to the test via "JDK-8244224: Implementation of JEP 381: Remove the Solaris and SPARC Ports".
Testing is mainly done on Ubuntu(18.04) and Fedora(version 32 and 33) and is a pass.

Note:
- I am actually resending this mail as it was not delivered earlier.
- Copyright year will be updated before push or if there are any other revisions to the patch.

Regards,
Ramanand.