Per https://w3c.github.io/webappsec-secure-contexts/, we are deprecating and then removing EME from insecure contexts. EME is a powerful feature that exposes DRM implementations that involve access to persistent unique identifiers, are not open source, and/or run unsandboxed or with privileged access. The risks are increased when exposed via insecure HTTP, because they could be attacked by anyone on the channel. This was deprecated in Chrome 44.
Docs: https://chromium.org/Home/chromium-security/deprecating-powerful-features-on-insecure-origins https://developer.mozilla.org/en-US/docs/Web/API/HTMLMediaElement/setMediaKeys