After I sent the original email I just changed
"mozilla-thunderbird-xpcom" in the configure.in to "xulrunner-xpcom"
and things built and ran fine. So I think that the IDL files needed
aren't necessarily Thunderbird-specific, they'll work against any
Mozilla-based product. How much those interfaces change between
products and between versions, I have no idea.
Oh yeah... Funny thing about .idl here which I just recalled. When I first started playing around with the IDL language I used the #include directive to include .idl files with stuff that I needed (the nsIMsgDBHdr interface for instance). It turned out that this didn't work well at all. It seemed like Thunderbird didn't identify types correctly in _javascript_ and I just kept getting exceptions thrown at me. I then changed to simple forward declarations instead and after that everything worked well. So I guess that the dependency disappeared after that.
The mozilla base is the same for all mozilla products but different products obviously add additional support for things needed. I have not idea what's the base and what's not though.
Do you know specifically what IDL files are required? Or is it just
the xpidl tool?