Fix SymDenotations#seesOpaques

Author: odersky

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

@@ -592,7 +592,7 @@ object SymDenotations {
 
     def seesOpaques(implicit ctx: Context): Boolean =
       containsOpaques ||
-      is(Module, butNot = Package) && owner.containsOpaques
+      is(Module, butNot = Package) && owner.seesOpaques
 
     /** Is this the denotation of a self symbol of some class?
      *  This is the case if one of two conditions holds:

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

@@ -2463,9 +2463,9 @@ class ExplainingTypeComparer(initctx: Context) extends TypeComparer(initctx) {
     if (skipped) op
     else {
       indent += 2
-      b append "\n" append (" " * indent) append "==> " append str
+      b.append("\n").append(" " * indent).append("==> ").append(str)
       val res = op
-      b append "\n" append (" " * indent) append "<== " append str append " = " append show(res)
+      b.append("\n").append(" " * indent).append("<== ").append(str).append(" = ").append(show(res))
       indent -= 2
       res
     }