fix by switching the getInterface implementation from setting Components.returnCode to throwing when an interface is not supported. Components.returnCode is currently broken (see bug 287107), and it's not clear when it gets fixed. The assertion is annoying and the original intent of returnCode was to use it for success codes anyway.
r=gavin
git-svn-id: svn://10.0.0.236/trunk@221940 18797224-902f-48f8-a5cc-f745e15eee43
