re-use remove_proxy in disconnect

Author: ianhi

lib/matplotlib/cbook.py

@@ -340,17 +340,12 @@ def disconnect(self, cid):
 
         No error is raised if such a callback does not exist.
         """
-        self._pickled_cids.discard(cid)
         for signal, proxy in self._func_cid_map:
             if self._func_cid_map[signal, proxy] == cid:
                 break
         else:  # Not found
             return
-        assert self.callbacks[signal][cid] == proxy
-        del self.callbacks[signal][cid]
-        self._func_cid_map.pop((signal, proxy))
-        if len(self.callbacks[signal]) == 0:  # Clean up empty dicts
-            del self.callbacks[signal]
+        self._remove_proxy(signal, proxy)
 
     def disconnect_func(self, signal, func):
         """