Similarly to how mcasas landed an HW overlay autotest ( crbug.com/865112 ), we'd like to have an end-to-end test for low latency.

While properly testing low latency (that it hits HW overlay and that latency is below a certain threshold) might not be easy, we could start testing those two properties separately. We could test we hit the HW overlay case for specific scenarios, and separately we can test that latency is below a certain threshold (lower than with normal compositing) for lowlatency canvases/apps.

My suggestions would be to start testing the WebGL case, and then add other scenarios like ARC++ low latency (that can be achieved with a wayland client) and so on.

Opening this bug to keep track of writing such tests.
Andres might have a few cycles to look into it and write a few tast tests.