address review: use tpe instead of typeOpt

Author: Jasper-M

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

@@ -704,7 +704,6 @@ trait Implicits { self: Typer =>
           params,
           args)
       }
-    def resolveTypes(targs: List[tpd.Tree])(implicit ctx: Context) = targs.map(a => fullyDefinedType(a.typeOpt, "type parameter", a.pos))
     arg.tpe match {
       case ambi: AmbiguousImplicits =>
         val maybeAnnot = ambi.alt1.ref.symbol.getAnnotation(defn.ImplicitAmbiguousAnnot).map(
@@ -721,6 +720,9 @@ trait Implicits { self: Typer =>
           }
           val args = alt.tree match {
             case TypeApply(_, targs) if params.nonEmpty =>
+              def resolveTypes(targs: List[tpd.Tree])(implicit ctx: Context) = {
+                targs.map(a => fullyDefinedType(a.tpe, "type parameter", a.pos))
+              }
               resolveTypes(targs)(ctx.fresh.setTyperState(alt.tstate))
             case _ =>
               Nil