My guess why Netfix works in Chrome 38+ is because it supports HTML5 with DRM (Media Source Extensions + Encrypted Media Extensions + Web Cryptography API). Netflix
announced native support in Safari with OS X Yosemite but it also works in Chrome 38+ and I believe Internet Explorer 11 too. More information about Netflix and HTML5 is available
here.
The reason why MC probably can't take advantage of it is because it's probably using older Chromium for rendering. Plus you'd need to change the user agent of MC to match what's accepted by Netflix to stream over HTML5. But other than that, it's not impossible that MC couldn't continue using Netflix using HTML5 as long as everything's supported on the Chromium side. Maybe the Internet Explorer side too, not sure. Assuming of course the HTML5 DRM stuff is part of the open-source code.