I've managed now to get cordova-android up and running with Joe's pluggable_webview branch, and the cordova-crosswalk-engine plugin, passing all of the mobile spec tests.
(I had a few tests in Contacts and Geolocation failing, but those were entirely due to timeouts; Contacts is *very* slow) My build is ARM-only, and there are some packaging issues to work through still, but I'm really happy with this so far. Its pretty amazing to just have to install a plugin, and have it swap in a modern webview, with, say, WebGL support out of the box. It's all dependent right now on the mods to cordova-android, which I'd really like to get out as part of 3.5.0. I'm going to try to merge that in soon, to give everyone a chance to test it out and make sure there aren't any regressions. Ian