Check whether a view lacks a bound variable

This is useful when I want to make a form add an option based on the level of the user. This test allows me to check that that information is missing when the current user does not have the required level.
make test fail if a view is not returned
Merge pull request #3917 from ravloony/4.1

[Proposal] Add an assertion that checks whether a view lacks a given variable. (Was against master branch)