Change test to make it pass

compileMixed failed because there was a cycle between immutable.Seq (compiled) and
parallel.ParSeq (loaded from classfile). Inspection of the completion log (turn completions
Printer on) and the stack trace showed that there's nothing we can do here. The old hk scheme
did not go into the cycle because it did not force an unrelated type. I believe with enough
tweaking we would also hva egotten a cycle in the old hk scheme.

The test is "fixed" by adding parallel.ParSeq to the files to compile.

Author: odersky

test/dotc/tests.scala

@@ -146,6 +146,7 @@ class tests extends CompilerTest {
   @Test def compileMixed = compileLine(
       """tests/pos/B.scala
         |./scala-scala/src/library/scala/collection/immutable/Seq.scala
+        |./scala-scala/src/library/scala/collection/parallel/ParSeq.scala
         |./scala-scala/src/library/scala/package.scala
         |./scala-scala/src/library/scala/collection/GenSeqLike.scala
         |./scala-scala/src/library/scala/collection/SeqLike.scala