8055767: Sjavac is leaking servers

Reviewed-by: alundblad, jfranck

langtools/src/jdk.compiler/share/classes/com/sun/tools/sjavac/server/SjavacServer.java

@@ -310,7 +310,7 @@ public class SjavacServer implements Terminable {
 
     @Override
     public void shutdown(String quitMsg) {
-        if (!keepAcceptingRequests.compareAndSet(false, true)) {
+        if (!keepAcceptingRequests.compareAndSet(true, false)) {
             // Already stopped, no need to shut down again
             return;
         }