Possible transitive cast prevents direct implicit cast

```haxe
class Main {
public static var views:IReadOnlyList;

static function main() {
views = [new Child()];
}
}

abstract IReadOnlyList(Array) from Array to Array {
// This method breaks compilation
// @:from static inline function fromList(list:List):IReadOnlyList {
// return cast list;
// }

public function new() {
this = [];
}
}

abstract List(Array) from Array to Array {
public inline function new() {
this = [];
}
}

class Base {
public function new() { }
}

class Child extends Base {
public function new() {super(); }
}
```
Uncommenting `@:from fromList` method breaks compilation:
```
Main.hx:5: characters 9-30 : Array should be IReadOnlyList
```