Knocking a few instructions off isSubType2, and...
Knocking a few instructions off isSubType2, and...

Knocking a few instructions off isSubType2, and dodging some list
traversals in SubstMap. Review by odersky.


jvican/scala,scala/scala,shimib/scala,scala/scala,slothspot/scala,jvican/scala,slothspot/scala,felixmulder/scala,lrytz/scala,felixmulder/scala,jvican/scala,lrytz/scala,shimib/scala,scala/scala,scala/scala,felixmulder/scala,jvican/scala,shimib/scala,slothspot/scala,slothspot/scala,shimib/scala,felixmulder/scala,lrytz/scala,martijnhoekstra/scala,lrytz/scala,felixmulder/scala,lrytz/scala,felixmulder/scala,jvican/scala,felixmulder/scala,shimib/scala,lrytz/scala,scala/scala,martijnhoekstra/scala,martijnhoekstra/scala,slothspot/scala,martijnhoekstra/scala,martijnhoekstra/scala,jvican/scala,slothspot/scala,martijnhoekstra/scala,slothspot/scala,shimib/scala,jvican/scala,scala/scala