Enable previously failing whitelist test

Author: odersky

test/dotc/scala-collections.whitelist

@@ -184,9 +184,7 @@
 ./scala-scala/src/library/scala/collection/SeqViewLike.scala
 ./scala-scala/src/library/scala/collection/mutable/IndexedSeqView.scala
 ./scala-scala/src/library/scala/collection/immutable/StreamViewLike.scala
-
-## This class causes a crash in backend -> @darkdimius
-#./scala-scala/src/library/scala/collection/immutable/TrieIterator.scala
+./scala-scala/src/library/scala/collection/immutable/TrieIterator.scala
 
 ./scala-scala/src/library/scala/collection/immutable/HashMap.scala
 ./scala-scala/src/library/scala/collection/immutable/HashSet.scala