force inlining and fix test

tests/unit/src/unit/issues/Issue3846.hx

@@ -6,11 +6,12 @@ package unit.issues;
 private class Extern {
 
 	@:keep
-	static function mytest(a:Dynamic) {
+	static public function mytest(a:Dynamic) {
 		return a;
 	}
 
     @:overload( function (a:Int):Dynamic {})
+	@:extern
     inline public static function test(a:String):Dynamic {
         return mytest(a);
     }

typer.ml

@@ -759,6 +759,7 @@ let unify_field_call ctx fa el args ret p inline =
 			   Related issue: https://github.com/HaxeFoundation/haxe/issues/3846
 			*)
 			cf.cf_expr <- cf0.cf_expr;
+			cf.cf_kind <- cf0.cf_kind;
 		| _ ->
 			()
 		end;