Place typeSimplifier as a member of Pickling

Author: noti0na1

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

@@ -50,6 +50,8 @@ class Pickler extends Phase {
  private val beforePickling = new mutable.HashMap[ClassSymbol, String]
  private val picklers = new mutable.HashMap[ClassSymbol, TastyPickler]
 
+ private val typeSimplifier = new TypeSimplifyTransformer
+
  /** Drop any elements of this list that are linked module classes of other elements in the list */
  private def dropCompanionModuleClasses(clss: List[ClassSymbol])(using Context): List[ClassSymbol] = {
  val companionModuleClasses =
@@ -61,8 +63,6 @@ class Pickler extends Phase {
  val unit = ctx.compilationUnit
  pickling.println(i"unpickling in run ${ctx.runId}")
 
- val typeSimplifier = new TypeSimplifyTransformer
-
  for
  cls <- dropCompanionModuleClasses(topLevelClasses(unit.tpdTree))
  tree <- sliceTopLevel(unit.tpdTree, cls)
@@ -137,9 +137,6 @@ class Pickler extends Phase {
  cls -> unpickler
  }
  pickling.println("************* entered toplevel ***********")
-
- val typeSimplifier = new TypeSimplifyTransformer
-
  for ((cls, unpickler) <- unpicklers) {
  val unpickled = typeSimplifier.transform(unpickler.rootTrees)
  testSame(i"$unpickled%\n%", beforePickling(cls), cls)