+ don't forget to shutdown the idlechecker thread

Author: oleksiys

providers/grizzly/src/main/java/org/asynchttpclient/providers/grizzly/GrizzlyAsyncHttpProvider.java

@@ -192,6 +192,10 @@ public void close() {
             }
             if (timeoutExecutor != null) {
                 timeoutExecutor.stop();
+                final ExecutorService threadPool = timeoutExecutor.getThreadPool();
+                if (threadPool != null) {
+                    threadPool.shutdownNow();
+                }
             }
         } catch (IOException ignored) { }