Fix bug in branch condition causing lambdas to be treated like scopes and not like functions.

jedi/api/classes.py

@@ -336,7 +336,7 @@ class BaseDefinition(object):
             raise AttributeError()
         followed = followed[0]  # only check the first one.
 
-        if followed.type == 'funcdef':
+        if followed.type in ('funcdef', 'lambda'):
             if isinstance(followed, er.InstanceElement):
                 params = followed.params[1:]
             else: