revert worker change

lib/datadog/core/workers/polling.rb

@@ -23,15 +23,6 @@ def perform(*args)
           end
         end
 
-        # Stops the worker thread.
-        #
-        # Signals the worker loop to stop and waits up to the timeout value
-        # (in seconds) for the thread to end.
-        # Then, if force_stop is true, terminates the thread by calling
-        # Thread#terminate.
-        #
-        # Returns true if the thread was terminated, false if the
-        # thread continues to run.
         def stop(force_stop = false, timeout = DEFAULT_SHUTDOWN_TIMEOUT)
           if running?
             # Attempt graceful stop and wait
@@ -43,9 +34,12 @@ def stop(force_stop = false, timeout = DEFAULT_SHUTDOWN_TIMEOUT)
                 "Timeout while waiting for worker to finish gracefully, forcing termination for: #{self}"
               end
               terminate
+            else
+              graceful
             end
+          else
+            false
           end
-          !running?
         end
 
         def enabled?