fix timing and failure handling in testRestartingExpiry

...which was failing nearly all the time on my laptop
- publishing is async, so we don't know when the message has it the
  server and hence the expiry timer starts. We could introduce a
  confirm, but it's easier to just use the server restart as an
  indicator.
- when the assertion fails we still need to delete the
  queue. otherwise other tests using the same queue name, but
  different params, will fail.

Author: rade

test/src/com/rabbitmq/client/test/functional/PerMessageTTL.java

@@ -69,12 +69,12 @@ public void testRestartingExpiry() throws Exception {
                         .build(), new byte[]{});
         long expiryStartTime = System.currentTimeMillis();
         restart();
-        long timeToExpiry = Integer.parseInt(expiryDelay) - (System.currentTimeMillis() - expiryStartTime);
-        if (timeToExpiry > 0L) {
-            Thread.sleep(timeToExpiry);
+        Thread.sleep(Integer.parseInt(expiryDelay));
+        try {
+            assertNull("Message should have expired after broker restart", get());
+        } finally {
+            deleteQueue(TTL_QUEUE_NAME);
         }
-        assertNull("Message should have expired after broker restart", get());
-        deleteQueue(TTL_QUEUE_NAME);
     }
 
 }