? extend T[] is not considered an array

[Attila Kelemen]

Hi,

I have not found anything in JLS specifically mentioning this. So, I'm not
sure if it is intentional, but the following code does not compile (in any
versions of Java I have tried):

```
interface ForEachable<T> {
  void forEach(Consumer<? super T> consumer);
}

List<String> wrongMethod(ForEachable<? extends String[]> arrays) {
  var result = new ArrayList<String>();
  arrays.forEach(array -> result.add(array[0]));
  return result;
}
```

or in an even simpler example:

```
String first(Supplier<? extends String[]> supplier) {
  return supplier.get()[0];
}
```

The compiler complains about `array[0]` that `array` is not an array. While
I get that the compiler cannot assume that there is no subtype of
`String[]`, but even if there was one, I would expect it to be an
array, and be indexable.

An obvious workaround is to assign `array` to a new local variable, but it
is awkward to do.

Is this behavior a bug, or something required by the JLS?

Thanks,
Attila
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