chore: add scala.language.2 to files in scala.ref

Author: hamzaremmal

library/src/scala/ref/PhantomReference.scala

@@ -12,6 +12,8 @@
 
 package scala.ref
 
+import scala.language.`2`
+
 class PhantomReference[+T <: AnyRef](value: T, queue: ReferenceQueue[T]) extends ReferenceWrapper[T] {
  val underlying: java.lang.ref.PhantomReference[_ <: T] =
  new PhantomReferenceWithWrapper[T](value, queue, this)

library/src/scala/ref/Reference.scala

@@ -12,6 +12,8 @@
 
 package scala.ref
 
+import scala.language.`2`
+
 /**
  * @see `java.lang.ref.Reference`
  */

library/src/scala/ref/ReferenceQueue.scala

@@ -12,6 +12,8 @@
 
 package scala.ref
 
+import scala.language.`2`
+
 class ReferenceQueue[+T <: AnyRef] {
 
  private[ref] val underlying: java.lang.ref.ReferenceQueue[_ <: T] = new java.lang.ref.ReferenceQueue[T]

library/src/scala/ref/ReferenceWrapper.scala

@@ -12,6 +12,7 @@
 
 package scala.ref
 
+import scala.language.`2`
 import scala.annotation.nowarn
 
 @nowarn("cat=deprecation")

library/src/scala/ref/SoftReference.scala

@@ -12,6 +12,8 @@
 
 package scala.ref
 
+import scala.language.`2`
+
 class SoftReference[+T <: AnyRef](value : T, queue : ReferenceQueue[T]) extends ReferenceWrapper[T] {
  def this(value : T) = this(value, null)
 

library/src/scala/ref/WeakReference.scala

@@ -12,6 +12,8 @@
 
 package scala.ref
 
+import scala.language.`2`
+
 /**
  * A wrapper class for java.lang.ref.WeakReference
  * The new functionality is (1) results are Option values, instead of using null.