Flag empty files inside a package (fix #334)

[tofumatt]

Internally flags all empty files inside addonMetadata without
throwing an error/raising any notices to the user, as requested
in #334.

[muffinresearch]

Can we determine from size metadata in both the XPI + file system cases? I also wonder if we also need a check to see if a file is just whitespace too?

[tofumatt]

That’s possible, yeah. This was my first-pass-simplest-thing try, but I suppose checking the unpacked size would work. I’ll try that.

[muffinresearch]

Yep yauzl iirc exposes unpacked size in the metadata object and the Directory class has just size which is from a stat object.

[tofumatt]

Cool; that is probably a bit faster too as we should already have the data. 👍

[tofumatt]

Using uncompressedSize now, should be a bit leaner/better!

[muffinresearch]

This API is different for the directory class [1].

Maybe we should add uncompressedSize as an alias? Either that or you need to check size too.

[1] https://github.com/mozilla/addons-validator/blob/master/src/io/utils.js#L21

[tofumatt]

I’d go for adding uncompressedSize as an alias; also means I should add an extra test for directories then. Thanks!

[tofumatt]

Actually, scrap that, seems cleaner to check for uncompressedSize then just size. I’ll have a patch in a few.

[tofumatt]

Pushed again; should be all set now.

[muffinresearch]

Lgtm. r+