Revert "Disable HEIC to JPEG conversion due to OOM errors, see https://reportedcab.slack.com/archives/C9VNM3DL4/p1613245801038700?thread_ts=1610546281.002400&cid=C9VNM3DL4"

[josephfrazier]

This reverts commit b32cb92.

WIP dump process.memoryUsage before/after HEIC conversion, see https://www.valentinog.com/blog/node-usage/

[josephfrazier]

From https://reportedcab.slack.com/archives/C9VNM3DL4/p1613254694046800?thread_ts=1610546281.002400&cid=C9VNM3DL4:

I added a bit of code before/after the HEIC/JPEG conversion locally to get a better idea of memory usage, from https://www.valentinog.com/blog/node-usage/

const used = process.memoryUsage();
for (let key in used) {
  console.log(`${key} ${Math.round(used[key] / 1024 / 1024 * 100) / 100} MB`);
}

and got the following output:

rss 104.16 MB
heapTotal 49.02 MB
heapUsed 45.49 MB
external 18.73 MB
arrayBuffers 17.19 MB
heic-convert: 5.374s
rss 513.46 MB
heapTotal 240.5 MB
heapUsed 213.47 MB
external 182.33 MB
arrayBuffers 180.79 MB

I don't know what all these numbers mean, but there's definitely a big jump after the heic-convert line, so I'm pretty confident that it's to blame for the OOM on heroku

[josephfrazier]

#266 would obviate this