SI-6535 Step back from the precipice of a cycle

Adding any non-local parent to WrapAsScala will trigger a valid
cyclic reference error. By moving the import of `Wrapper._`
inside `WrapAsScala` and `WrapAsJava`, it is not in scope when
typing the parents of those, and we avoid the cycle.

Adds a test case to show the essense of the promiscious mutual
imports that triggers this.

1 files changed, 15 insertions, 0 deletions

diff --git a/test/files/neg/t6535.scala b/test/files/neg/t6535.scala
new file mode 100644
index 0000000000..30a750311c
--- /dev/null
+++ b/test/files/neg/t6535.scala
@@ -0,0 +1,15 @@
+object As {
+  import Bs.B._
+
+  object A
+  extends scala.AnyRef // needed for the cycle;
+                       // replacing with a locally defined closs doesn't
+                       // hit the locked import and hence doesn't cycle.
+}
+
+object Bs {
+  import As.A._
+
+  object B
+  extends scala.AnyRef // scala.Immutable, ...
+}