File contains two classes (one class and one interface), the mock-object
interface was missing resolution for Constraint.
This Constraint is PHPUnit\Framework\Constraint\Constraint.
Phpunit upstream indents (prefixes) docblock @param annotations and I can
imagine that some white-space has been taken over from that into the stub
files when writing them.
Also for separation by empty lines between methods which looks as well
as an error quickly porting from upstream (better than anything else).
