Chrome Version: 60.0.3096.0 (Official Build) canary (64-bit)

What steps will reproduce the problem?
(1) Go to https://beaufortfrancois.github.io/sandbox/media/hd.html
(2) Accept gUM permission prompt

What is the expected result?
Enjoy watching myself

What happens instead?
I don't look like I am in the mirror

I'd argue { facingMode: 'user' } gUM media constraint should return a mirrored version of the video stream - by default.
Manipulating bytes before drawing them in a canvas is doable but this is not what we expect as users and developers so let's make the default experience better by default.