SI-6201 minor fixes in key points
SI-6201 minor fixes in key points

Fixes several oversights that led to 6201. RootPackage should have been static,
refactored implementation of hasSymbolWhich shouldn't have checked hasSymbol.

Full discussion is here:
http://groups.google.com/group/scala-internals/browse_thread/thread/9500348f273a8aa.

SethTisue/scala-xml,ashawley/scala-xml,biswanaths/scala-xml