In connection with "[SPR-11126] problem converting empty parameter to

List", 
the resolveName(String, MethodParameter, NativeWebRequest) method
in the RequestParamMethodArgumentResolver.java has been slightly
chagned.
In case that MethodParameter is related to List type,
String[](with legnth 1) value will be returned itself
without being changed to String.

Issue : SPR-11126