Unbraced statements spanning multiple lines has been shown in many
projects to contribute to the introduction of bugs and a failure
to catch them in review, especially for maintenance on infrequently
modified code.
Most, but not all, of the existing practice in the codebase were not
cases that I would have expected to eventually result in bugs but
applying it as a rule makes it easier for other people to safely
contribute.
I'm not aware of any such evidence for the case with the statement
on a single line, but some people strongly prefer to never do that
and the opposite rule of "_always_ use a single line for single
statement blocks" isn't a reasonable rule for formatting reasons.
Might as well brace all these too, since that's more universally
acceptable.
[In any case, I seem to have introduced the vast majority of the
single-line form (as they're my preference where they fit).]
This also removes a broken test which is no longer needed.