5cb9aa9cf3
Instead of manually tracking source icon changes, or requiring a manual call to _setSummaryIcon, add a way to emit a signal when we're guaranteed the icon has been changed, and then the source actor will automatically update the icon. _setSummaryIcon is still available for sources such as the notification daemon, that require special treatment for the summary icon (to be used with tray icons) https://bugzilla.gnome.org/show_bug.cgi?id=680426