Following up on things that -Xlint told me, som...

Following up on things that -Xlint told me, sometimes because Mr. Linty
was being sensible and other times just to shut him up so we can hear
better in the future.

- made xml.Equality public because it occurs in public method signatures
- made some actor classes with inaccessible-unoverridable methods final
- eliminated a bunch of "dead code follows" warnings by deleting the
dead code which really did follow - improved the reliability of warnings
about inaccessible types

For the changes in actors, review by phaller.

Author: paulp

src/library/scala/xml/Attribute.scala

@@ -15,8 +15,8 @@ package scala.xml
 
 object Attribute {
   def unapply(x: Attribute) = x match {
-    case PrefixedAttribute(_, key, value, next) => Some(key, value, next)
-    case UnprefixedAttribute(key, value, next)  => Some(key, value, next)
+    case PrefixedAttribute(_, key, value, next) => Some((key, value, next))
+    case UnprefixedAttribute(key, value, next)  => Some((key, value, next))
     case _                                      => None
   }
 

src/library/scala/xml/Equality.scala

@@ -65,7 +65,6 @@ object Equality {
 }
 import Equality._
 
-private[xml]
 trait Equality extends scala.Equals {
   def basisForHashCode: Seq[Any]
   def strict_==(other: Equality): Boolean

src/library/scala/xml/PrefixedAttribute.scala

@@ -53,5 +53,5 @@ extends Attribute
 }
 
 object PrefixedAttribute {
-  def unapply(x: PrefixedAttribute) = Some(x.pre, x.key, x.value, x.next)
+  def unapply(x: PrefixedAttribute) = Some((x.pre, x.key, x.value, x.next))
 }

src/library/scala/xml/UnprefixedAttribute.scala

@@ -56,5 +56,5 @@ extends Attribute
     next(namespace, scope, key)
 }
 object UnprefixedAttribute {
-  def unapply(x: UnprefixedAttribute) = Some(x.key, x.value, x.next)
+  def unapply(x: UnprefixedAttribute) = Some((x.key, x.value, x.next))
 }