message: Improve error mapper
diff: @@ -122,15 +122,9 @@ pub trait Querier {
  &self,
  request: &QueryRequest<C>,
  ) -> StdResult<U> {
  - let raw = match to_vec(request) {
  - Ok(raw) => raw,
  - Err(e) => {
  - return Err(StdError::generic_err(format!(
  - "Serializing QueryRequest: {}",
  - e
  - )))
  - }
  - };
  + let raw = to_vec(request).map_err(|serialize_err| {
  + StdError::generic_err(format!("Serializing QueryRequest: {}", serialize_err))
  + })?;
  match self.raw_query(&raw) {
  SystemResult::Err(system_err) => Err(StdError::generic_err(format!(
  "Querier system error: {}",
  