Fix bad `this` value in React native plugin (fixes #468)
Fix bad `this` value in React native plugin (fixes #468)

getsentry/raven-js,getsentry/raven-js,Mappy/raven-js,getsentry/raven-js,housinghq/main-raven-js,getsentry/raven-js,Mappy/raven-js,housinghq/main-raven-js,Mappy/raven-js,housinghq/main-raven-js