Further legacy support, error handling, plus minor fixes.
This is a relatively minor release. All it does is implement support for webRTCNonProxiedUdpEnabled
only if the browser is Chromium 47 based.
It also implements low-level error handling, and fixes several very minor issues.
The previous version was 1.0.4. I've pushed it up to 1.0.9 to match the main extension.