Skip Java using run test when scalajs

Author: dwijnand

compiler/test/dotty/tools/vulpix/ParallelTesting.scala

@@ -751,8 +751,11 @@ trait ParallelTesting extends RunnerOrchestration { self =>
           case _ =>
         }
         case Failure(output) =>
-          echo(s"Test '${testSource.title}' failed with output:")
-          echo(output)
+          if output == "" then
+            echo(s"Test '${testSource.title}' failed with no output")
+          else
+            echo(s"Test '${testSource.title}' failed with output:")
+            echo(output)
           failTestSource(testSource)
         case Timeout =>
           echo("failed because test " + testSource.title + " timed out")

tests/run/i17021.ext-java/Test.scala

@@ -1,3 +1,4 @@
+// scalajs: --skip
 // Derives from run/i17021.defs
 // but with a Java protected member
 // and fixed calling code, that uses super