Better window.onerror toggle api (.collectWindowErrors)

[devinrhode2]

In another library I was working on, I figured a very seamless way to offer a boolean toggle is to just have a function that you pass in true/false.

My proposal is changing collectWindowErrors to be a function instead of boolean switch like: TraceKit.collectWindowErrors(false) Then, when you turn off window errors, we also restore the previous window.onerror handler, when you turn them on, we restore our handler.

Any tweaks or good to go?

[niemyjski]

@devinrhode2, why not just have it so you have to buy into wiring up to global event handlers?