Regression: error on New Tab in Firefox

[max-baz]

It is supposed to show a full list of passwords, and it definitely worked like this in the past, not sure when it broke:

[erayd]

Probably our origin change. I'll fix this one too.

[erayd]

The root cause of this appears to be a bug in Firefox's URL parsing, which returns a string "null" instead of an actual null value for the origin property under some circumstances.

I'm getting sick of just how many Firefox bugs I keep running into, particularly when contrasted with Chrome, where the APIs generally behave according to the spec.

I'm implementing a workaround.