Rollup merge of #99489 - GuillaumeGomez:gui-fixes, r=notriddle

Rollup merge of #99489 - GuillaumeGomez:gui-fixes, r=notriddle

rustdoc UI fixes

The first commit fixes this bug:

![Screenshot from 2022-07-20 02-54-26](https://user-images.githubusercontent.com/3050060/179879053-fc34f27a-6248-4f5c-9fcb-80adbfc1598c.png)
![Screenshot from 2022-07-20 03-00-03](https://user-images.githubusercontent.com/3050060/179879056-1c0973a0-d535-44e7-a48e-bad692034467.png)

The second one fixes the missing change of border color when the search input is focused.

cc `@jsha`
r? `@notriddle`