Version: 62.0.3202.75 (32/64-bit)67b212ffb03c4401235f8961e2d15371b96cde27-refs/branch-heads/3202@{#750}
OS: Windows (7,8,8.1,10),Linux (14.04 LTS),Mac OS X(10.12.6,10.13.6)

What steps will reproduce the problem?
1. Launch chrome, navigate to chrome://settings and open devtools and open emulated view.
2. Now go to 'Element' section and go to 'Properties' and open console drawer by pressing 'Esc' key.
3. Now expand 'getBoundingClientRect' code line and double click on argument to open 'Type Error:' text.
4. Now move cursor ahead using right arrow key and the try to move horizontal scroll bar to RHS,observe(Refer screen cast)

Actual: Horizontal scroll bar doesn't move smoothly(It goes back and forward while dragging ahead)
Expected: Horizontal scroll bar should move smoothly

This is regression issue, broken in ‘M 56’ and below is the bisect results:
Good build:55.0.2883.0 (Revision: 423769)
Bad build: 56.0.2886.0 (Revision: 424099)

You are probably looking for a change made after 424034 (known good), but no lat
er than 424035 (first known bad).

CHANGELOG URL:

The script might not always return single CL as suspect as some perf builds might get missing due to failure.

https://chromium.googlesource.com/chromium/src/+log/5dfbc0a96c848ec1e232d543921330cc7aaa15f4..c320a900cd8320048e1e1f553cdc01f2633c68b3

From the CL above, assigning the issue to the concern owner 

@dgozman- 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.

Suspect : https://chromium.googlesource.com/chromium/src/+/c320a900cd8320048e1e1f553cdc01f2633c68b3

Thanks!
 

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	Actual_video.mp4 1.3 MB View Download

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	Expected_video.mp4 979 KB View Download