Arvados

This may be due to the work from #4464 (where manifest text is omitted while loading projects -> Data collections tab).

I went back to my local version of the branch used to review this branch (at 7c5a88d) and see the issue there as well.

Sorry I did not notice this issue during the review phase of this branch.

Tom said on IRC:

12:11 tomclegg: I'm inclined to say 5185 should be: step 1. Don't say "0 bytes" when we don't have the information, just leave that column blank. step 2. With full text search we can make the "list of files" attr complete, instead of truncating it; and we can add sizes to it while we're at it. Caching the total data size seems like a good idea, following the same pattern as the computed "list of files" attr.
12:12 tomclegg: When API offers that attr, workbench should request it, and use that to display the collection size.
12:13 tomclegg: But yes, I think we should do the trivial fix now. It's too bad we lose the file size but I think that's better than super-slow/timing-out page loading, in the interim.

Implemented Step 1: if description is available, display it in the description column; otherwise display the modified time.