Chrome version : 70.0.3537.0 (Official Build) Revision 57f65e033d6d9160457a612f5033171bdfeaca42-refs/branch-heads/3537@{#1}(32/64-bit) 
OS :Win(7,8,8.1,10) ,Mac(10.12.6 , 10.13.1 , 10.13.6, 10.14) and Linux(14.04 LTS)  OS

Pre-condition: Enable "Enable using the Google local NTP" ,"New Tab Page Background Selection" and "New Tab Page Custom Links" flags under chrome://flags.

Steps to reproduce:
1. Fresh launch chrome and open NTP.
2. Click on 'Add Shortcut' icon and add a new shortcut to NTP.
3. Observe that a confirmation message of 'Shortcut added' along with 'Undo' and 'Restore default shortcuts' buttons is seen.
4. While the 'Shortcut added' message is still visible remove the added shortcut.
5. Observe that a confirmation message of 'Shortcut removed' along with 'Undo' and 'Restore default shortcuts' buttons is seen.
6. Now again Click on 'Add Shortcut' icon and add a new shortcut and observe the confirmation message for added shortcut.

Actual Result  :The confirmation message 'Shortcut added' appears for a brief time but does not stay.
Expected Result:The confirmation message 'Shortcut added' should appear and stay for a specific time.

This is a regression issue broken in ‘M-70’ and below is bisect info.
Good build: 70.0.3535.0(Revision: 586475)
Bad build : 70.0.3536.0(Revision: 587136)

Narrow bisect info:

https://chromium.googlesource.com/chromium/src/+log/	3d7ed512a06dd88c86c416df97afb701317485a9..78867c06919268e1d1f1af9ccea9c0a96e550eaf?pretty=fuller&n=50

Suspecting: https://chromium.googlesource.com/chromium/src/+/200d9e4f2ee5303d58c735b9067fb7d92e40ec37

@kristipark: Could you please look into the issue, pardon me if it has nothing to do with your changes and if possible please assign it to concern owner.

Note:
Tried per revision bisect on Windows ,Mac and Linux OS but unable to perform the same since getting following errors 
(a)[Errno 2] No such file or directory error message is thrown on Mac OS and
(b)Unable to find local data files error is thrown on Windows,Linux OS, hence providing narrow bisect

Thank You

 

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	ActualVideo.mov 4.5 MB View Download

Deleted: ExpectedVideo.mov 5.1 MB

	ExpectedVideo.mov 5.1 MB View Download