Chrome version: 70.0.3514.0 (Official Build)Revision e359e11e00b7a42e1b5f7fee1f89b38a48c2dc60-refs/branch-heads/3514@{#1}(32/64-bit)
OS: Windows (7,8,8.1,10)

What steps will reproduce the problem?
1. Launch chrome,navigate to NTP and open devtools
2. Now go to 'Memory' section and press 'Esc' key to open 'Console' drawer and then hover mouse over '>>' chevron icon and observe
 
Actual: Unnecessary scoll bar appears/disappers after hovering mouse over '>>' chevron icon
Expected: Unnecessary scoll bar shouldn't appear/disapper after hovering mouse over '>>' chevron icon

This is regression issue, broken in ‘M 69’ and will soon update other info :
Good build: 69.0.3489.0  (Revision: 574446).
Bad build: 69.0.3491.0 (Revision: 575129).

You are probably looking for a change made after 574888 (known good), but no later than 574893 (first known bad).

Narrow Bisect info : 
https://chromium.googlesource.com/chromium/src/+log/bdb7c6bf6d378e95ddeb81014e30bb19cdd87c86..a9b528a9d90a7542ce9f797a1b3728626f0e9eaf?pretty=fuller&n=50

Suspecting: r574889 from Narrow bisect

@kylixrd: Could you please help to reassign if your change is not the cause for this change.

Note:
1.Unable to provide bisect using per-revision script,Hence providing chromium bisect.
2.Issue is not seen on Mac(10.12.6,10.13.1,10.13.6) and Linux (14.04 LTS) OS
3.Issue is only reproducible for device monitors with screen resolution 1280 X 1024
 

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