What does this console message mean in Google App Engine
This seems to happen if you have async operations in progress before you enter the ndb.toplevel function.
My guess is that this warns you that theses async operations will not be waited for at the end of the request. This could be an issue if you expected them to be included in your "toplevel" function and they are tasklets waiting for an operation to complete before executing some more.
I'm using Google App Engine NDB with a lot of async operations and yields. The console shows me this message:

tasklets.py:119] all_pending: clear set([Future 106470190 created by
  dispatch(webapp2.py:570) for tasklet post(sync.py:387); pending])

Is this a warning of some sort? Should it be ignored? It doesn't cause any unusual behavior.
(sync.py is one of my files, but the other stuff aren't mine)