corruption when open/save with v0.34.0: Error: Trailer

[gwik]

Hi,

When opening and saving a PDF the resulting PDF is corrupt and cannot be opened by lopdf with release 0.34.

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut pdf = lopdf::Document::load("doc.pdf")?;

    pdf.save("/tmp/test.pdf")?;
    lopdf::Document::load("/tmp/test.pdf")?;

    Ok(())
}
// Error: Trailer

The problem was fixed by 443ab33

Can you please make a new release?

A workaround is to remove the "Prev" entry from the trailer before save.

pdf.trailer.remove(b"Prev");