Remove the strange return values from visi_leaf.

parso/python/normalizer.py

@@ -92,8 +92,6 @@ class ErrorFinder(Normalizer):
                         message = "'continue' not supported inside 'finally' clause"
                         self._add_syntax_error(message, leaf)
 
-        return ''
-
     def _add_indentation_error(self, message, spacing):
         self._add_error(903, "IndentationError: " + message, spacing)
 

parso/python/pep8.py

@@ -367,8 +367,6 @@ class PEP8Normalizer(ErrorFinder):
 
         self._previous_leaf = leaf
 
-        return leaf.value
-
     def _visit_part(self, part, spacing, leaf):
         value = part.value
         type_ = part.type