Use base types to compute classOf args of applyDynamic

As suggested in #11043 (comment)

Fixes #11043

Author: mbovel

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

@@ -268,7 +268,7 @@ trait Dynamic {
             if tpe.paramInfoss.nestedExists(!TypeErasure.hasStableErasure(_)) then
               fail(i"has a parameter type with an unstable erasure") :: Nil
             else
-              TypeErasure.erasure(tpe).asInstanceOf[MethodType].paramInfos.map(clsOf(_))
+              tpe.paramInfoss.flatten.map(tp => clsOf(tp.baseType(tp.classSymbol)))
           structuralCall(nme.applyDynamic, classOfs).maybeBoxingCast(tpe.finalResultType)
         }
 

tests/pos/i11043.scala

@@ -0,0 +1,14 @@
+import scala.reflect.Selectable.reflectiveSelectable
+
+object Test {
+  type Runner = { def run(args: Array[String]): Unit }
+
+  def test(args: Array[String], runner: Runner): Unit =
+    runner.run(args)
+
+  def main(args: Array[String]): Unit = {
+    test(Array("foo", "bar"), new {
+      def run(args: Array[String]): Unit = args foreach println
+    })
+  }
+}

tests/pos/i11043min.scala

@@ -0,0 +1,5 @@
+import scala.reflect.Selectable.reflectiveSelectable
+
+type Runner = { def run(args: Array[String]): Unit }
+
+def test(runner: Runner): Unit = runner.run(???)