solve 0 key see as no key

[arfost]

Actualy when a key is set to 0, the firebase-document think that there is no key, but firebase can self generate key at 0 from array, and the concerned item will be untouchable.

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[arfost]

I signed it!

[googlebot]

CLAs look good, thanks!

[mbleigh]

Can you also add a breaking test case that is fixed by your PR?

[arfost]

Thanks for the answer, I did the check change, for the test i'm still new to polymer and firebase, and not exactly sure on how to do it for now. I'll look it up tonight to learn and will do it tomorrow if i think i'm good to go or ask for help if not :)

[arfost]

Ok, I looked into the test things, and I'm not sure of what I have to do. It seems that the firebase-document tests are from an external lib. Should I modify this external file or add a single test in the firebase-document test file ? Or am I way out, and it's something totally different ?

[justweb1]

@arfost You add firebase-document test file in the tests directory

[tjmonsi]

I think we can add a test later? I'm going to check up on this, this weekend

[merlinnot]

I’ll add a test for this in the coming days so we can proceed. I’d also like to revert the change requested by @mbleigh per https://github.com/firebase/polymerfire/pull/142#discussion_r159987448

Is it ok?