[add-art dev] versionsplash hackery

[Jamie Wilkinson]

Been fighting around with the versionsplash branch the last few hours  
so that we can put out a release on Thursday that says "Firefox3  
support coming soon". Matt kicked ass on the branch, but there's still  
an issue with it not working on the very first launch.

Localized the bug to nsIExtensionManager.getItemForID('development at add-art.org 
') not finding the extension... *but only on the very first launch*.  
Tried using the alt ID {349823-3489234802...} etc. but no dice. Tried  
a couple other bits of code to do getItemForID-style but no dice.

I added exception handling that fakes the current version at 0.0.0  
(since it can't get the addon to find out what the real version is).

This results in the "YOU DID IT!" screen showing up twice, once the  
first time (at 0.0.0 "first install") and then again on second launch,  
when you're upgrading from 0.0.0 to the real current version. I figure  
this is better than the splash only showing up on the second launch.

Been hitting folks up on IRC but everyone else has this shit working  
just fine!!#$#@
Best docs so far are here:
http://developer.mozilla.org/en/docs/Code_snippets:On_page_load

nsIExtensionManager.getItemList seems like a nice place to start  
debugging (e.g. see if the extension is available on the first launch)  
but I'm calling it quits for tonight

-jamie