Reported by: Yakov Shafranovich (yakovsh@amazon.com)

Currently, `ObjectInputStream::readObject()` doesn't explicitly checks for a negative array length in the deserialization stream. Instead it calls `j.l.r.Array::newInstance(..)` with the negative length which results in a `NegativeArraySizeException`. NegativeArraySizeException is an unchecked exception which is neither declared in the signature of `ObjectInputStream::readObject()` nor mentioned in its API specification. It is therefore not obvious for users of `ObjectInputStream::readObject()` that they may have to handle `NegativeArraySizeException`s. It would therefor be better if a negative array length in the deserialization stream would be automatically wrapped in an `InvalidClassException` which is a checked exception (derived from `IOException` via `ObjectStreamException`) and declared in the signature of `ObjectInputStream::readObject()`.

If we do the negative array length check in `ObjectInputStream::readObject()` before filtering, this will then also fix `ObjectInputFilter.FilterInfo::arrayLength()` which is defined as:
```
Returns:
the non-negative number of array elements when deserializing an array of the class, otherwise -1
```
but currently returns a negative value if the array length is negative.