WIP: Fix Rails multi-exception reports

[nateberkopec]

No description provided.

[nateberkopec]

ping @mattrobenolt

This fixes the issue for the app you provided in #388, and, as far as I can tell, doesn't break any additional use cases. Can you take a look?

[nateberkopec]

Can also confirm this works correctly with rescue_from - errors which are not re-raised by rescue_from are not reported.

[greysteil]

👍 ❤️

[mattrobenolt]

I tested this locally, and it seems to record the wrong one now.

It only logged one event, but it only logged the event wiht the url of /500, not the original url. So seems like we're filtering out the wrong one.

[mattrobenolt]

For posterity, I ran against my docker container:

$ docker run --rm --name=sentry-test -e RAILS_ENV=production -e SENTRY_DSN=https://xxx:xxx@app.getsentry.com/3825 -p 3000:3000 -v $PWD:/usr/src/app -v /Users/matt/code/getsentry/raven-ruby:/usr/local/bundle/gems/sentry-raven-0.15.2 -it sentry-test

And mounted in this PR.

Without mounting this in, it was recording the error twice. Now only records once, but the wrong one.

[nateberkopec]

For posterity: I worked this out with @mattrobenolt and made sure the right exception was recorded.