I think most of the commenters are basing their responses on the (terrible) headline rather than what actually seems to have happened.

As comment 19 of the bug report says, "This bug is not about to implement HEVC in Chrome", and "Chrome does already support the native HEVC decoder for progressive download videos using the HTML5 <video> tag on Android". The issue description notes that as of Feb 2015, "Playing plain HEVC mp4 files in Chrome/Android/Nexus5 works fine".

This new fix just corrects the handling of HEVC in the Chrome's Media Source API (formerly known as "Media Source Extensions").