Stop! Bracket style!

We should adhere to WordPress coding styles, particularly with respect to [brackets in conditionals](https://make.wordpress.org/core/handbook/coding-standards/php/#brace-style).

This style:

``` php
if ( stuff_exists() )
do_a_thing();
```

Should be:

``` php
if ( stuff_exists() ) {
do_a_thing();
}
```

No files or tests are named. Locate PHP conditionals that omit braces and compare them with the linked WordPress brace-style guidance; done means the applicable conditionals in the repository follow that style without changing behavior.

Written by the indexing model from the issue text.