In React-Native document gets set sometimes without a location object

[rmevans9]

This is a bug in TraceKit but not sure which TraceKit repository the file stored in this repo is pulled from.

Currently in my React Native app document gets set by one of the libraries used (not sure which.... just know it does with just a single property on the object). When an exception occurs and raven attempts to log that error out to Sentry (or wherever it is setup to log) the logging of the error blows up as well.

I would expect that it can handle the document object not having a location property.

The fix is to modify https://github.com/getsentry/raven-js/blob/master/vendor/TraceKit/tracekit.js#L27 to be more tolerant to the location property being undefined. I can submit a PR but want to figure out which repo that fix really should go into so that it propagates to this project so that I can start logging errors in React Native correctly.

[mattrobenolt]

We have our own fully vendored and highly modified version of TraceKit that we use internally, so if you'd like to submit a PR, this is the best place. :)