Chrome 37 has a blob+IndexedDB bug

[nolanlawson]

Looks like we need to write a workaround for this: https://code.google.com/p/chromium/issues/detail?id=408120.

The fix will come in 38, but while 37 is still in the wild, we have to live with it.

[nolanlawson]

I can confirm the bug in Chrome 37. I have both 36 and 37 installed, and the error only manifests in 37.

Luckily, the tests in #2705 are enough to suss out this error.

[nolanlawson]

Well, this actually turned out to be a different problem. In both Chrome 37 and Chrome 39, I see that when you use the FileReader on an empty Blob, it gives you back an undefined body instead of an empty one. So that's an easy fix.

As for the other bug, it seems to either have been backported to 37, or it just doesn't affect us at all. I cannot distinguish between Firefox and Chrome 37 when it comes to the content-type of stored blobs (or anything else about the blobs).

[nolanlawson]

Never mind, I can repro this issue.

Opening another issue for the other one.

[calvinmetcalf]

merged