[opus] Chrome 33 released with Opus support in HTML <audio>

[Ralph Giles]

Mark Edwards just pointed out to me that Chrome 33 is now in stable
release. That means that by default, Chrome users can play Opus files.

In addition to using Opus with WebRTC connections, M33 is the first
release with default support for .opus encapsulated files and http(s)
streams. Congratulations, Google!

In my quick testing it played all my music files, including surround,
and respected the gain and end-trim features. It doesn't play chained
files, and for some reason won't play the conformance test vectors.

 -r