New component in xulrunner

[Mike Hommey]

Hi,

In the upcoming 1.9.1.6-2 release of xulrunner, I added a new
(experimental) component (technically, 2 tied together) that tracks file
changes in key directories so that the user can be notified of system
upgrades for extensions, plugins, xulrunner itself, or the application.

It should work properly in most XUL applications, if they emit a
final-ui-startup notification, but I would like to hear from XUL apps
maintainers to know if that really works as expected.

Cheers,

Mike