Returns whether the annotation's optional content (OC) leaves it visible in state.
public bool IsVisible(PdfOptionalContentState state)
Group states from the document's OptionalContent, such as its default states.
ISO 32000-2 §12.5.2, Table 166 (OC, PDF 1.5), and §8.11.3.3, through IsVisible(CosObject?, PdfOptionalContentState).