The ripple on mat-button extends to corners

[mertdeg2]

Bug, feature request, or proposal:

Bug

What is the expected behavior?

When user clicks on the button, ripple goes till rounded corners, but it does not fully extend till rectangular corners.

What is the current behavior?

Ripple extends till corners. This is hard to see but added a video.

What are the steps to reproduce?

https://angular-5xca8e.stackblitz.io/
(Try zooming 500%)

[mertdeg2]

[angular-automatic-lock-bot]

This issue has been automatically locked due to inactivity.
Please file a new issue if you are encountering a similar or related problem.

Read more about our automatic conversation locking policy.

_{This action has been performed automatically by a bot.}