SI-8911 scala.collection.convert.Wrappers$MapWrapper not serializable

Added `with Serializable` to `MapWrapper` and `SetWrapper`.

Test verifies that serialization works in the simplest case.

Also updated tests in t8549 to check that serialization works and doesn't change.

1 files changed, 5 insertions, 4 deletions

diff --git a/src/library/scala/collection/convert/Wrappers.scala b/src/library/scala/collection/convert/Wrappers.scala
index 9f9732c62f..c2da66a9bf 100644
--- a/src/library/scala/collection/convert/Wrappers.scala
+++ b/src/library/scala/collection/convert/Wrappers.scala
@@ -102,9 +102,9 @@ private[collection] trait Wrappers {
     override def clone(): JListWrapper[A] = JListWrapper(new ju.ArrayList[A](underlying))
   }
 
-  // Note various overrides to avoid performance gotchas.
-  class SetWrapper[A](underlying: Set[A]) extends ju.AbstractSet[A] {
-    self =>
+  @SerialVersionUID(1L)
+  class SetWrapper[A](underlying: Set[A]) extends ju.AbstractSet[A] with Serializable { self =>
+    // Note various overrides to avoid performance gotchas.
     override def contains(o: Object): Boolean = {
       try { underlying.contains(o.asInstanceOf[A]) }
       catch { case cce: ClassCastException => false }
@@ -165,7 +165,8 @@ private[collection] trait Wrappers {
       new JSetWrapper[A](new ju.LinkedHashSet[A](underlying))
   }
 
-  class MapWrapper[A, B](underlying: Map[A, B]) extends ju.AbstractMap[A, B] { self =>
+  @SerialVersionUID(1L)
+  class MapWrapper[A, B](underlying: Map[A, B]) extends ju.AbstractMap[A, B] with Serializable { self =>
     override def size = underlying.size
 
     override def get(key: AnyRef): B = try {