Bump Scala version in Scala example. Add hack for Scala runtime.

classlib/src/main/java/org/teavm/classlib/impl/ScalaHacks.java

@@ -46,6 +46,9 @@ public class ScalaHacks implements ClassHolderTransformer {
             case "scala.util.Properties$":
                 transformProperties(cls);
                 break;
+            case "scala.runtime.Statics":
+                transformStatics(cls, context.getHierarchy());
+                break;
             default:
                 if (cls.getName().endsWith(SCALA_INTERNAL_CLASS_MARKER)) {
                     checkAndRemoveExportAnnotation(cls);
@@ -97,6 +100,15 @@ public class ScalaHacks implements ClassHolderTransformer {
         }
     }
 
+    private void transformStatics(ClassHolder cls, ClassHierarchy hierarchy) {
+        for (MethodHolder method : cls.getMethods()) {
+            if (method.getName().equals("releaseFence")) {
+                ProgramEmitter pe = ProgramEmitter.create(method, hierarchy);
+                pe.exit();
+            }
+        }
+    }
+
     private void checkAndRemoveExportAnnotation(ClassHolder cls) {
         for (MethodHolder method : cls.getMethods()) {
             AnnotationContainer items = method.getAnnotations();

samples/scala/pom.xml

@@ -15,7 +15,7 @@
 
   <properties>
     <java.version>1.8</java.version>
-    <scala.version>2.12.11</scala.version>
+    <scala.version>2.13.8</scala.version>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
   </properties>
   
@@ -45,7 +45,7 @@
       <plugin>
         <groupId>net.alchim31.maven</groupId>
         <artifactId>scala-maven-plugin</artifactId>
-        <version>4.3.1</version>
+        <version>4.6.1</version>
         <executions>
           <execution>
             <goals>

samples/scala/src/main/scala/org/teavm/samples/scala/Calculator.scala

@@ -52,7 +52,7 @@ object Calculator {
 
   def keyword(str: String) = s(str) ~ ws >> { case (s, _) => s }
 
-  def ws = s(" ").* >> (_ => Unit)
+  def ws = s(" ").* >> (_ => ())
 }
 
 sealed abstract class Expr