message: introduce a new helper, `verify_inputs`
diff: @@ -185,7 +185,7 @@ where
  // first things first, let's walk over each of our previous
  // inputs and check whether they are out of date.
  if let Some(QueryState::Memoized(old_memo)) = &mut old_value {
  - if old_memo.validate_memoized_value(db) {
  + if old_memo.verify_memoized_value(db) {
  debug!("{:?}({:?}): inputs still valid", Q::default(), key);
  // If none of out inputs have changed since the last time we refreshed
  // our value, then our value must still be good. We'll just patch
  @@ -337,11 +337,7 @@ where
  _ => unreachable!(),
  };
  - if memo
  - .inputs
  - .iter()
  - .all(|old_input| !old_input.maybe_changed_since(db, memo.verified_at))
  - {
  + if memo.verify_inputs(db) {
  memo.verified_at = revision_now;
  self.overwrite_placeholder(&mut self.map.write(), key, QueryState::Memoized(memo));
  return false;
  @@ -385,12 +381,16 @@ where
  Q: QueryFunction<DB>,
  DB: Database,
  {
  - fn validate_memoized_value(&self, db: &DB) -> bool {
  + fn verify_memoized_value(&self, db: &DB) -> bool {
  // If we don't have a memoized value, nothing to validate.
  if !self.value.is_some() {
  return false;
  }
  + self.verify_inputs(db)
  + }
  +
  + fn verify_inputs(&self, db: &DB) -> bool {
  match self.changed_at {
  ChangedAt::Revision(revision) => self
  .inputs
  