extend-edit-sequence-queue

• (send a-mred:media-edit extend-edit-sequence-queue l) -> void
      l : a list of thunks

  This procedure should only be called from after-edit-sequence. It extends the edit-sequence queue (see run-after-edit-sequence) with the list of thunks. This is used when a wx:media-edit% object finishes an edit-sequence, but some containing edit is still in an edit sequence. The method is called to pass of then contained edit's list of thunks to the containing edit.