`phutil_symbols.php` does not correctly handle static method calls. I believe that a static method call can only happen on a class, not an interface.
```lang=php, name=test.php
<?php
Foo::bar();
```
```lang=bash
> ./scripts/phutil_symbols.php test.php
{
"have": [],
"need": {
"class\/interface": {
"Foo": 7
}
},
"xmap": []
}
```