Chrome version :50.0.2661.26 0abdf9cbb43ea5639687aa21a2bcb206b1dc6d7b-refs/branch-heads/2661@{#169} (32/64 bit)
OS : Windows(Win 7 aero enabled).

Steps : 
1. Launch Chrome and open NTP and open devtools
2. Now go to 'Sources' section and click on 'Hide navigator' icon and observe the tool tip

Actual : 'Show navigator' tool tip is misplaced after clicking 'Hide navigator' icon
Expected : 'Show navigator' tool tip should not get misplaced after clicking 'Hide navigator' icon

This is a regression issue broken in 'M-46' and below is the manual regression and narrow bisect info:
Good build : 46.0.2486.0
Bad build : 46.0.2487.3

Narrow bisect :
https://chromium.googlesource.com/chromium/src/+log/f8b4519cadf7dea1e6c6c5337afc5da5e73e5548..31f8bdbaac5826a596bc71dfb2b271715c85fcbe?pretty=fuller&n=50

Blink bisect :
https://chromium.googlesource.com/chromium/blink/+log/365bf7a..6e764452b4a59f8bb3bd3a856dd597b8515d8679?pretty=fuller&n=50

Suspecting : 200712 from Blink bisect.

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

Note : Issue is not seen on Mac and Linux OS.
 

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Actual_video.mp4 369 KB Download

Deleted: Expected_video.mp4 544 KB

Expected_video.mp4 544 KB Download

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	Actual_screenshot.png 103 KB View Download

Deleted: Expected_screenshot.png 110 KB

	Expected_screenshot.png 110 KB View Download