Allow client to force server to terminate if it exits

This is intended to be used by screen lockers, where the server must
exit if the screen locker does, to avoid a security hole.  As suggested
by Alan Coopersmith, this is implemented using a new flag for the
disconnect mode of the XFixes extension.
9 jobs for DemiMarie-master-patch-34896 in 2 minutes and 14 seconds (queued for 4 seconds)
latest
Status Job ID Name Coverage
  Prep
passed container-prep #12235318

00:00:24

 
  Build
passed autotools: [] #12235321

00:01:17

passed autotools: [--enable-legacy] #12235322

00:01:16

passed meson: [] #12235319

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passed meson: [-Dlegacy=true] #12235320

00:00:53

 
  Test
passed check evdev keysyms #12235325

00:00:10

passed check versions are in sync #12235326

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passed compare meson and autotools #12235324

00:00:23

passed meson from tarball #12235323

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