<AWT Dev> <AWT dev>[9] Review request for 8156121: "Fail forward" fails for GTK3 if no GTK2 available

[Semyon Sadetsky]

Hello,

Please review fix for JDK9:

bug: https://bugs.openjdk.java.net/browse/JDK-8156121

webrev: http://cr.openjdk.java.net/~ssadetsky/8156121/webrev.00/

The issue is caused by changes in -Djdk.gtk.version=<gtk version> 
specification. Initially it should be working as a constraint:  only 
allow the specified version of GTK lib (don't use GTK if this version is 
not available). Then after discussions the specification was amended to 
use this property as a advise: the GTK version to start loading with (if 
it fails the next available GTK version will be attempted). So that, the 
code need be harmonized with the specification.

--Semyon