Inline unapplys in the inlining phase

These currently got inlined while typing. Therefore they used to generate
code that should not be pickled.

Author: nicolasstucki

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

@@ -90,6 +90,11 @@ class Inlining extends MacroTransform, IdentityDenotTransformer {
           else super.transform(tree)
         case _: Typed | _: Block =>
           super.transform(tree)
+        case tree: UnApply =>
+          tree match
+            case tree1: UnApply if Inlines.needsInlining(tree1) =>
+              super.transform(cpy.UnApply(tree1)(fun = Inlines.inlinedUnapplyFun(tree1.fun)))
+            case tree1 => super.transform(tree1)
         case _ if Inlines.needsInlining(tree) =>
           val tree1 = super.transform(tree)
           if tree1.tpe.isError then tree1

compiler/src/dotty/tools/dotc/typer/Typer.scala

@@ -1942,9 +1942,6 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
             if (bounds != null) sym.info = bounds
           }
           b
-        case t: UnApply if t.symbol.is(Inline) =>
-          assert(!t.symbol.is(Transparent))
-          cpy.UnApply(t)(fun = Inlines.inlinedUnapplyFun(t.fun)) // TODO inline these in the inlining phase (see #19382)
         case t => t
       }
   }