- Fix unused parameters warnings
- Change call to openDeclaration to send an Identifier instead of an QualifiedIdentifier
What the deprecated method does:
```
auto openDeclaration(QualifiedIdentifier x, ...) {
Identifier i;
if (!x.isEmpty()) {
i = x.last();
}
return openDeclaration(i, ...);
}
```
This does remove a check to isEmpty().