Chrome Version       : 63.0.3232 (Canary)
OS Version: OS X 10.12.6

What steps will reproduce the problem?
1. On Mac system preferences, turn on "Full keyboard access"
2. goto a site e.g. https://permission.site, and allow or deny some permissions by clicking on the buttons on the page and accepting/blocking
3. Cmd+L to access to Omnibox, and then Shift+Tab to select the security chip
4. Space to open page info
5. Tab, tab,,, to a permission dropdown
6. Change status
7. Observe where the focus moves
8. And also, try to navigate to other permission dropdown

Screen recording: go/piosx6303232kn

What is the expected result?
- Focus remains to the interacted dropdown, or moves to next dropdown if the dropdown row is removed
- Still be able to navigate to all dropdowns on the UI after interacting with a dropdown


What happens instead of that?

- Focusring disappears
- All dropdowns on the UI are no longer reachable via keyboard after interacting with a dropdown
- Only non-dropdown controls, i.e. links, are reachable via keyboard