modif comment.

theano/gof/env.py

@@ -291,7 +291,7 @@ class Env(utils.object2):
         current value of node.inputs[i] which we want to replace.
 
         For each feature that has a 'on_change_input' method, calls:
-          feature.on_change_input(env, node, i, old_r, new_r)
+          feature.on_change_input(env, node, i, old_r, new_r, [reason])
         """
         # TODO: ERROR HANDLING FOR LISTENERS (should it complete the change or revert it?)
         if node == 'output':