[display] "find references" on get/set modifiers still returns garbage in some cases

Trying to invoke "find references" on `get`/`set` specifiers of `I.field` will return some random positions.

```haxe
class Main {
static function main() {
var c = new C();
var f = c.field;
c.field = f;
}
}

class C implements I {
public var field(get,set):Int;
public function new() {}

function get_field() return 10;
function set_field(value:Int) return value;
}

interface I {
var field(get,set):Int;
}
```