In JavaScript, when there isn't a `break` or `return` statement inside a
`switch` case, the next case will be executed as well.
That wasn't a problem here because CoffeeScript automatically inserts a
`return` statement in this specific situation. However, since we don't
want to return the result of the `hide()` operation, it might be easy to
accidentally remove the `return` statement, causing the code to break.
I've added a test for the scenario where neither `break` nor `return`
statements are present, so we don't run into this error.
The `type: :feature` is automatically detected by RSpec because these
tests are inside the `spec/features` folder. Using `feature` re-adds a
`type: :feature` to these files, which will result in a conflict when we
upgrade to Rails 5.1's system tests.
Because of this change, we also need to change `background` to `before`
or else these tests will fail.
Show a flash message that it's not possible to delete booth shifts
when they have associated recounts or partial results. Before an
execption was raised.
