Chrome Version : 71.0.3578.80 (Official Build) 2ac50e7249fbd55e6f517a28131605c9fb9fe897-refs/branch-heads/3578@{#860} 64 bit
OS : Mac(10.13.6, 10.13.1, 10.14.2)

Test URL : https://mounirlamouri.github.io/sandbox/media/dynamic-controls.html

What steps will reproduce the problem?
1. Launch chrome, navigate to above test URL and press ‘TAB’ key thrice to bring focus on ‘Volume’ slider.
2. Now, press and hold ‘Left/Right’ Arrow keys from keyboard to increase or decrease volume slider.
3. Observe.

Actual Result : Speed of volume slider is slightly slower than expected, when using keyboard shortcuts.

Expected Result : Volume slider should have slightly better speed when using keyboard shortcuts to increase or decrease volume.

This is a regression issue broken in M-71 and below is the bisect information:
Good Build : 71.0.3571.0 (Revision : 596951)
Bad Build : 71.0.3572.0 (Revision : 597445)

Change-Log URL:
https://chromium.googlesource.com/chromium/src/+log/4ce54aef688da6e101194ba3bb99a9f3254ea478..ab76b11dae74e3e7739e5d8b15088909c4b357cb

Suspect: https://chromium.googlesource.com/chromium/src/+/ab76b11dae74e3e7739e5d8b15088909c4b357cb

@steimel: Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

Note:
1. This is Mac OS specific issue and same is working fine in Windows(7,8,10) and Linux(14.04 LTS) OS
2. Issue is reproducible in Dev #72.0.3622.0 and Canary build #73.0.3629.0

Thank you..!
 

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