Return query block even if no value exists

[davedbase]

When submitting multiple queries (or a single query) it would be a good idea of the response at least propagated an empty block namespace. Take for example:

{
  CheckUsername(func: has(Account)) @filter(eq(Account, "foobar")) {
    Exists : count(Email)
  }
  CheckEmail(func: has(Account)) @filter(eq(Email, "[email protected]")) {
    Exists : count(Account)
  }
}

If neither account values are found the response is completely empty. It would be great if at least the response came back with an empty property that can be checked against (for consistency).