Fix compilation failure in LambdaLift

Author: odersky

compiler/src/dotty/tools/dotc/core/StdNames.scala

@@ -24,7 +24,7 @@ object StdNames {
     final val SHADOWED_PREFIX          = "(shadowed)"
     final val AVOID_CLASH_SUFFIX       = "$_avoid_name_clash_$"
     final val MODULE_SUFFIX            = "$"
-    //final val NAME_JOIN                = "$"
+    final val NAME_JOIN                = "$"
     final val DEFAULT_GETTER           = "$default$"
     final val LOCALDUMMY_PREFIX        = "<local "       // owner of local blocks
     final val ANON_CLASS               = "$anon"

compiler/src/dotty/tools/dotc/transform/LambdaLift.scala

@@ -8,7 +8,7 @@ import core.Contexts._
 import core.Types._
 import core.Flags._
 import core.Decorators._
-import core.StdNames.nme
+import core.StdNames.{nme, str}
 import core.Names._
 import core.NameOps._
 import core.Phases._
@@ -22,7 +22,7 @@ import collection.{ mutable, immutable }
 import collection.mutable.{ HashMap, HashSet, LinkedHashMap, LinkedHashSet, TreeSet }
 
 object LambdaLift {
-  private val NJ = NameTransformer.NAME_JOIN_STRING
+  private val NJ = str.NAME_JOIN
   private class NoPath extends Exception
 }