Make GDK_BACKEND=x11 the default

[pefribeiro]

It seems as of recent Ubuntu updates, there is a potential issue running Eclipse on Linux, when under Wayland, that causes it to crash as noted in several forums online and the Eclipse bugtrack, resulting in an exception similar to the following:

(Eclipse:712811): Gdk-CRITICAL **: 15:06:31.978: gdk_window_create_gl_context: assertion 'GDK_IS_WINDOW (window)' failed
#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00007f8b802c88b8, pid=712811, tid=712812
#
# JRE version: OpenJDK Runtime Environment (19.0.2+7) (build 19.0.2+7-Ubuntu-0ubuntu322.04)
# Java VM: OpenJDK 64-Bit Server VM (19.0.2+7-Ubuntu-0ubuntu322.04, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# C  [libwebkit2gtk-4.0.so.37+0xdba8b8]
#
# Core dump will be written. Default location: Core dumps may be processed with "/usr/share/apport/apport -p%p -s%s -c%c -d%d -P%P -u%u -g%g -- %E" (or dumping to /scratch/pfr500/eclipse/java-latest-released/core.712811)
#
# An error report file with more information is saved as:
# /scratch/pfr500/eclipse/java-latest-released/hs_err_pid712811.log
#
# If you would like to submit a bug report, please visit:
#   Unknown
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#

This seems to affect different Eclipse versions. Usually we instruct users to run Eclipse under X11, even if on Wayland, eg. passing GDK_BACKEND=x11 on the command line. In any case, the packaged installs produced from this repository should enable this flag is enabled by default, if possible, so I'm making a note here for potential improvement.

[pefribeiro]

Other related workarounds discussed here.