Chrome app and window history

[dikaso]

Raven throws error when used inside Chrome App.

TypeError: Cannot read property 'pushState' of null

Here is the line https://github.com/getsentry/raven-js/blob/master/dist/raven.js#L957

It looks like window.history is disabled in Chrome App https://developer.chrome.com/apps/app_deprecated

[benvinegar]

Interesting, so 'history' in window is true, but it's null or something. I'll just beef up this check.

[dikaso]

I can confirm that fix works.