8003280: Add lambda tests

Turn on lambda expression, method reference and default method support

Reviewed-by: jjg

langtools/test/tools/javac/defaultMethods/syntax/TestDefaultMethodsSyntax.java

@@ -54,7 +54,7 @@ public class TestDefaultMethodsSyntax {
         }
 
         List<String> getOptions() {
-            return Arrays.asList("-XDallowDefaultMethods", "-source", versionString);
+            return Arrays.asList("-source", versionString);
         }
     }