Add more varargs tests

Also move some disabled tests to run tests,
and rename vararg-extend-java to varargs-extend-java

Author: TheElectronWill

tests/disabled/java-interop/failing/t1459/AbstractBase.java

@@ -0,0 +1,10 @@
+import scala.annotation.varargs
+
+abstract class Abs {
+  @varargs def counter(s: String*) = ()
+}
+
+trait T {
+  @varargs def counter(s: String*): Unit
+}
+

tests/disabled/java-interop/failing/t1459/App.scala

@@ -0,0 +1,14 @@
+import scala.annotation.varargs
+
+class Impl extends Abs {
+  override def counter(s: String*): Unit = ()
+}
+
+trait B extends T {
+  override def counter(s: String*): Unit = ()
+}
+
+class C extends B {
+  override def counter(s: String*) = ()
+}
+

tests/disabled/java-interop/failing/t2569/Child.scala

@@ -0,0 +1,5 @@
+package base;
+
+public abstract class AbstractBase {
+    public abstract void doStuff(Object... params);
+}

tests/disabled/java-interop/failing/t2569/Parent.java

@@ -2,6 +2,7 @@
 
 public class Caller {
    public void callDoStuff(AbstractBase impl) {
-       impl.doStuff("abc"); // was new Object());
+       impl.doStuff("abc");
+       impl.doStuff(new Object());
    }
-}
+}

tests/disabled/java-interop/failing/varargs-bridge/A.java

@@ -0,0 +1,13 @@
+import base._
+
+object Test extends App {
+  class Concrete extends AbstractBase {
+     override def doStuff(params: AnyRef*): Unit = println("doStuff invoked")
+  }
+
+  val impl = Concrete()
+  impl.doStuff(null)
+
+  val caller = Caller()
+  caller.callDoStuff(impl)
+}