Progress of GZIP data appears to calculate from compressed size

[bitwisecook]

Small description When opening a log that's gzip'd the progress percent appears to be calculated from the compressed size. Here I'm using f5log, internally that just uses iterload() with no wrapper for progress.

Expected result Parsing should finish at 100%

Actual result with screenshot

Steps to reproduce with sample data and a .vd Open any compressed log large enough to take time to parse and go to shift-S. sheets.vd.txt

Additional context 2.9.0-dev with f5log 0.2.4

[anjakefala]

Most likely related to https://github.com/saulpw/visidata/issues/1175 =)