Use WrappedArray’s iterableFactory for ArraySeq

The old AraySeq was never specialized, so this is the closest
equivalent that we have.

Author: szeiger

collections/src/main/scala/strawman/collection/mutable/package.scala

@@ -3,10 +3,10 @@ package strawman.collection
 import scala.deprecated
 
 package object mutable {
-  @deprecated("Use WrappedArray instead of ArraySeq", "2.13.0")
+  @deprecated("Use WrappedArray instead of ArraySeq; it can represent both, boxed and unboxed arrays", "2.13.0")
   type ArraySeq[X] = WrappedArray[X]
-  @deprecated("Use WrappedArray instead of ArraySeq", "2.13.0")
-  val ArraySeq = WrappedArray
+  @deprecated("Use WrappedArray instead of ArraySeq; it can represent both, boxed and unboxed arrays", "2.13.0")
+  val ArraySeq = WrappedArray.untagged
   @deprecated("Use Iterable instead of Traversable", "2.13.0")
   type Traversable[X] = Iterable[X]
   @deprecated("Use Iterable instead of Traversable", "2.13.0")