Calling addAll on itself causes OOM

[Praveen Balaji]

This code causes OOM:

public class OOM {
    public static void main(final String[] args) {
        final TIntArrayList a = new TIntArrayList();
        a.add(1);
        a.addAll(a);
    }
}

Could probably instead do what java.util.ArrayList does:

ensureCapacityInternal(size + numNew);
System.arraycopy(a, 0, elementData, size, numNew);

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