workspace: Activate window when close dialog gets shown

Use the new close-dialog-visible signal of MetaWindow to activate a
non-responding window which we tried to close before as soon as the
close dialog is shown.

Also don't show the close button of the window overlay in case the close
button is visible since the window requires the user to interact with
the dialog anyway.

GNOME/gnome-shell!550
4 jobs for !550 with overview-show-window-on-close-dialog in 14 minutes and 10 seconds (queued for 2 seconds)
latest detached
Status Job ID Name Coverage
  Review
passed #305936
check_commit_log

00:00:22

 
  Build
passed #305937
build

00:12:35

 
  Test
passed #305938
test

00:01:04

passed #305939
test-pot

00:01:11