after we show the helper app dialog. So progress and load information is
now retargeted to a stand alone window instead of re-using the underlying
browser / mail window...In order to do this, the external app handler needed to implement nsIURIContentListener.
sr=r=rpotts
code review will come when this is done and gets turned on.
Add a private interface to be shared between the os specific helper app service and the external app handler
for launching an app.
mscott%netscape.com