Steps to reproduce the problem:
1. put device at rest on a leveled surface
2. set device orientation lock to off
3. enter the test page, record its initial orientation type with screen orientation API(`screen.orientation.type`)
4. rotate to orientation type (`screen.orientation.lock("...")`)
5. unlock the screen orientation (`screen.orientation.unlock()`)

code snippet:
let initial_type = screen.orientation.type; // e.g. portrait-primary
screen.orientation.lock("landscape-primary");
screen.orientation.unlock();
let current_type = screen.orientation.type; //landscape-primary
assert_equals(initial_type, current_type); //false

What is the expected behavior?
current screen orientation type is equals to the initial one

What went wrong?
they are different

Did this work before? N/A 

Does this work in other browsers? N/A

Chrome version: 71.0.3557.2  Channel: canary
OS Version: 7.1.1
Flash Version: 

Spec link: https://w3c.github.io/screen-orientation/