Expose name() of senders

Change-Id: Ia1e97cf5dc8f1e92728626b21fcf1b7f4da4e6b1
diff --git a/aos/events/raw-event-loop.h b/aos/events/raw-event-loop.h
index ffc894b..a903e93 100644
--- a/aos/events/raw-event-loop.h
+++ b/aos/events/raw-event-loop.h
@@ -60,6 +60,8 @@
     Free(reinterpret_cast<SendContext *>(t));
   }
 
+  virtual const char *name() const = 0;
+
  protected:
   RawSender(const RawSender &) = delete;
   RawSender &operator=(const RawSender &) = delete;