Chrome Version:64.0.3274.0/10151.0.0 dev channel Swanky
OS:Chrome OS

What steps will reproduce the problem?
(1)Launch chrome >>Open devtools page[on R.H.S]and Observe its frame on L.H.S 

Actual:Border frame is seen missing for Devtools on L.H.S 
Expected:Border frame for devtools page should be seen

This is a Regression issue as same is working fine in M-56

Note:
1.Issue is not seen in Linux,Windows OS and also in other chrome OS devices like Candy,Kip,Gnawty,glimmer which belongs to the same board rambi
2.Able to reproduce the issue on latest M-62 stable channel swanky

@allada: Please confirm the issue
 

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	actual.png 721 KB View Download

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	Expected.jpg 219 KB View Download