2.8.0.RC3 => 2.8.0.RC4 : override def with var broken

[scabug]

scala> trait Foo[X] { def foo : Map[String,Foo[X]] }
defined trait Foo

scala> def f[T]() : Foo[T] = new Foo[T] { var foo = Map[String,Foo[T]]() }
f: [T]()Foo[T]

And now leads to:

<console>:6: error: object creation impossible, since method foo in trait Foo of type => Map[String,Foo[T]] is not defined
       def f[T]() : Foo[T] = new Foo[T] { var foo = Map[String,Foo[T]]() }

[scabug]

Imported From: https://issues.scala-lang.org/browse/SI-3560?orig=1
Reporter: Francois Armand (fanf)

[scabug]

@paulp said:
Fixed formatting and trimmed summary. Easy to spot since there weren't many suspects: introduced in r22184, right here:

-              member.setFlag(PRIVATE)
-              member.privateWithin = NoSymbol
+              member.privateWithin = classDef.symbol

[scabug]

@odersky said:
(In r22253) Closes #3174 and #3560. Review by moors.

[scabug]

@odersky said:
(In r22254) Applied patch that closes #3560 and still fixes #3174.