1480000 - Update style for animation playback rates button and dropdown

Status: NEW

(DevTools :: Inspector: Animations, defect, P5)

Description

[Cristian Fogel, QA [:cfogel]]

Attachment: animations_ratesButtonDropdown.png

[Affected versions]:
-Firefox  63.0a1 (2018-07-31), 61.0.1, 62.0b12, 60.0.2ESR;
[Affected platforms]:
- All supported

[Steps to reproduce]:
1. Launch Firefox;
2. Access the following link:
https://rawgit.com/dadaa/3b73f847427025b51ba1ab7333013d0c/raw/77f3f0bb884875a179c3407f73bf8a8dd54751c9/doc_simple_animation.html
3. Open DevTools, Inspector - Animations tab;
4. Hover over the button for setting speed rates;
5. Click on that button.

[Expected result]:
- style is similar to other buttons, dropdown menus

[Actual result]:
- style is outdated, check attachment

[Additional notes]:
- attached screenshot;
- 52ESR could also benefit from this update.