Log the error message when retrying queue send

service/src/main/java/org/whispersystems/textsecuregcm/websocket/WebSocketConnection.java

@@ -258,6 +258,8 @@ public class WebSocketConnection implements MessageAvailabilityListener, Displac
             processStoredMessages();
           }
         } else {
+          logger.debug("Failed to clear queue", cause);
+
           if (consecutiveRetries.incrementAndGet() > MAX_CONSECUTIVE_RETRIES) {
             client.close(1011, "Failed to retrieve messages");
           } else {