screenShield: Wake up on deactivate()

Usually the screen is woken up before the shield is deactivated, but
it is also possible to unlock the session programmatically via the
org.gnome.ScreenSaver D-Bus API.

The intention is very likely not to unlock a turned off screen in
that case. Nor does it seem like a good idea to change the lock
state without any indication.

Waking up the screen is more likely to meet expectations and is
more reasonable too, so do that.

https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1158


(cherry picked from commit fbe2e30f38)

js/ui/screenShield.js

@@ -498,6 +498,8 @@ var ScreenShield = class {
         if (Main.sessionMode.currentMode == 'unlock-dialog')
             Main.sessionMode.popMode('unlock-dialog');
 
+        this.emit('wake-up-screen');
+
         if (this._isGreeter) {
             // We don't want to "deactivate" any more than
             // this. In particular, we don't want to drop