Switcher: accessibility: When switching between panel Compiz doesn't send events to accessibility bus

Hello all,

Environment:

• Debian Testing/Buster
• Compiz 2:0.8.16.1-8

Steps to reproduce:

1. Add a shortcut to switch to the next panel, here control + alt + tab (don't forget to remove the assigned shortcut on next window (all))
2. Launch the Orca screen reader
3. Press the defined shortcut

Result with Compiz 0.8: Orca doesn't announce the new panel

Result with Compiz 0.9: Orca announces the new selected panel

It's gtk-window-decorator that should emit accessibility events for the such case but it emits nothing in this case.

Best regards, Alex.