We are currently patching `@babel/runtime` to fix various lockdown
errors caused by `@babel/runtime` modifying globals as part of various
polyfills. There was one lockdown error that was showing up in Sentry
error reports, which is the polyfill used for `Reflect.construct`.
All of our supported browsers include this API, so the polyfill has
been replaced with a Proxy that returns the `Reflect.construct`
function directly, except with the addition of the `default` and
`__esModule` properties. I don't know what these properties are for
(maybe ES5/ES6 interoperability?) but I left them just in case they
were being relied upon.
