Seen on: 59.0.3070.0 canary

Steps to reproduce
1. Pin enough items to the shelf so that the overflow button appears.
2. With touch, swipe up from the bottom of the screen to start the "shelf stretching" animation, but do not release the finger.
3. With mouse, click underneath the overflow arrow.

What happens:
The overflow button is targeted.

What should happen instead:
The overflow button should not be targeted.

Note: the incorrect bounds can be visualized by following the repro steps of  issue 714265 .