Version: 57.0.2929.0 dev
OS: Ubuntu 14.04, Windows

What steps will reproduce the problem?
(1)Launch Chrome and go to https://www.youtube.com/.
(2)Play any video and press F12 to open devtools.
(3)Now click on "Toggle device mode" and in mobile view click on Youtube home button.
(4)Press F12 to exit from Devtools and observe.(refer attached screen cast)

Expected: After exiting from devtools, page shouldn't throw any error.
Actual: Instead, error is seen on page.

This is a regression issue broken in M 49.

Note 1: This issue is not seen if we sign into Chrome.
Note 2: Blank pages are seen from 49.0.2567.0 to 54.0.2817.0 builds after step (4).
From 54.0.2819.0, error page is seen after step (4).

Manual Bisect Range:
========================
Good build: 48.0.2564.0
Bad build: 49.0.2567.0 

Below is the Tool Bisect Info:
CHANGELOG URL:
https://chromium.googlesource.com/chromium/src/+log/a2e8a4030fc3da64a9d3c261fc5402213dcc443d..b0ed7040ca6afc56499cec7ea410962cd5322090

Suspecting https://codereview.chromium.org/1450133003

@dgozman : Please feel free to re-assign if this is not related to your change

 

Deleted: actual_youtube_error.ogv 3.7 MB

	actual_youtube_error.ogv 3.7 MB View Download

Deleted: actual_youtube_blank.ogv 5.7 MB

	actual_youtube_blank.ogv 5.7 MB View Download

Deleted: expected_youtube.ogv 4.9 MB

	expected_youtube.ogv 4.9 MB View Download