Chrome Version : 70.0.3517.0 (Official Build) 40b8dc74d4eba316ce85e7c7cb5cac598d17069d-refs/branch-heads/3517@{#1} 64 bit
OS : Mac(10.12.6, 10.13.1, 10.13.6, 10.14)

Test URL : https://googlechrome.github.io/samples/picture-in-picture/

What steps will reproduce the problem?
1. Launch chrome and navigate to above test URL.
2. Click on three dot menu and select 'Picture in Picture' option.
3. Close the PiP video frame using 'Close' (X) icon.
4. Again switch to 'Picture in Picture' mode and hover mouse over video.
5. Observe the PiP video frame.

Actual Result : 'Play' & 'Close' media controls are not visible on mouse hover in PiP video frame for second instance.

Expected Result : 'Play' & 'Close' media controls should be shown in PiP video when user hover mouse over the video.

This is a regression issue broken in ‘M-70’ and providing the bisect using per-revision script :
Good Build : 70.0.3511.0 (Revision : 580407)
Bad Build : 70.0.3512.0 (Revision : 580755)

You are probably looking for a change made after 580456 (known good), but no later than 580457 (first known bad)

Change Log URL :
https://chromium.googlesource.com/chromium/src/+log/7a07960a925b2b0c2e8dc5e9b49f349fb5bd3e7a..6698555a6f8132847bd6198fa4d39a507999d6cd

Suspecting : https://chromium.googlesource.com/chromium/src/+/6698555a6f8132847bd6198fa4d39a507999d6cd

Jennifer@ : 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 not reproducible in Windows(7,8,8.1,10) & Linux(14.04 LTS) OS.
2. This issue is also observed in Mac Dev build #70.0.3514.2

Thank You..!
 

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