Correction: 
Chrome Version: 61.0.3163.59 (Official Build)9577e0b56f9184a32f33705fabfc6bf5c2d1d4a3-refs/branch-heads/3163@{#773} 32/64-bit.

Using the per-revision bisect providing the bisect results,
Good build: 61.0.3150.0
Bad build: 61.0.3152.0

You are probably looking for a change made after 484746 (known good), but no later than 484758 (first known bad).

CHANGELOG URL:
The script might not always return single CL as suspect as some perf builds might get missing due to failure.

https://chromium.googlesource.com/chromium/src/+/9c35b80be7b82051abec46fabdcdef6be4b214a2

From the CL above, assigning the issue to the concern owner

@ananta: 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.

Review-URL: https://codereview.chromium.org/2972963004

Note :Able to reproduce the issue in Win 10.0,Ubuntu 14.04 & Mac 10.126 and able to reproduce in latest Canary #62.0.3194.0

Adding Blocker label, please remove if not the case.

URGENT - PTAL.
M61 Stable promotion is coming VERY soon and your bug is labelled as Stable ReleaseBlock, pls make sure to land the fix and get it merged into the release branch ASAP. 

Know that this issue shouldn't block the release?  Remove the ReleaseBlock-Stable label or move to M62. Thank you!

Note: Plan is to cut M61 Stable RC on 08/31/17.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f091c0c1b2a968a5f61dc15da2b35b87077d077a

commit f091c0c1b2a968a5f61dc15da2b35b87077d077a
Author: Anantanarayanan Iyengar <ananta@chromium.org>
Date: Fri Aug 25 23:30:55 2017

Fix a regression on Windows 7 which manifested in normal windows obscuring the taskbar when a fullscreen window is around.

This bug only occurs on Windows 7 and started with my change where we use the ITaskbarList2::MarkFullscreenWindow() API
to inform the taskbar about a window being fullsceen or not. As per docs calling this API when a window goes fullscreen is enough
for the taskbar to hide itself when that window is active and to show itself when the window is inactive. It appears that the behavior
is different on Windows 7.

The fix being tried here is to mark the window as fullscreen when it is active and inactive when it is not, i.e a manual process.
This works fine on Windows 7 and 10 and was verified by QA.

BUG= 758113 

Change-Id: Ibdeae0be10640559594fe97980b622d64ae6ae75
Reviewed-on: https://chromium-review.googlesource.com/634451
Commit-Queue: Ananta Iyengar <ananta@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#497593}
[modify] https://crrev.com/f091c0c1b2a968a5f61dc15da2b35b87077d077a/ui/views/win/fullscreen_handler.cc
[modify] https://crrev.com/f091c0c1b2a968a5f61dc15da2b35b87077d077a/ui/views/win/fullscreen_handler.h
[modify] https://crrev.com/f091c0c1b2a968a5f61dc15da2b35b87077d077a/ui/views/win/hwnd_message_handler.cc

Update : 
Retested above issue in latest chrome canary #62.0.3198.0 on Windows 7 OS and issue is not reproducible. Issue is fixed now and it is working as intended.
Kindly review an attached screen cast.

Thank you!

Deleted: Canary_Behaviour.mp4 813 KB

	Canary_Behaviour.mp4 813 KB View Download

This bug requires manual review: We are only 7 days from stable.
Please contact the milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), ketakid@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Approving merge to M61 branch 3163 based on comment #6 and per offline chat with Ananta & Prudhvi.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/854c089d7063043bc260865aeeb77dc6a1d1a793

commit 854c089d7063043bc260865aeeb77dc6a1d1a793
Author: Anantanarayanan Iyengar <ananta@chromium.org>
Date: Tue Aug 29 01:12:33 2017

Fix a regression on Windows 7 which manifested in normal windows obscuring the taskbar when a fullscreen window is around.

Merging to M61

This bug only occurs on Windows 7 and started with my change where we use the ITaskbarList2::MarkFullscreenWindow() API
to inform the taskbar about a window being fullsceen or not. As per docs calling this API when a window goes fullscreen is enough
for the taskbar to hide itself when that window is active and to show itself when the window is inactive. It appears that the behavior
is different on Windows 7.

The fix being tried here is to mark the window as fullscreen when it is active and inactive when it is not, i.e a manual process.
This works fine on Windows 7 and 10 and was verified by QA.

BUG= 758113 
TBR=ananta@chromium.org

(cherry picked from commit f091c0c1b2a968a5f61dc15da2b35b87077d077a)

Change-Id: Ibdeae0be10640559594fe97980b622d64ae6ae75
Reviewed-on: https://chromium-review.googlesource.com/634451
Commit-Queue: Ananta Iyengar <ananta@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#497593}
Reviewed-on: https://chromium-review.googlesource.com/640070
Reviewed-by: Ananta Iyengar <ananta@chromium.org>
Cr-Commit-Position: refs/branch-heads/3163@{#961}
Cr-Branched-From: ff259bab28b35d242e10186cd63af7ed404fae0d-refs/heads/master@{#488528}
[modify] https://crrev.com/854c089d7063043bc260865aeeb77dc6a1d1a793/ui/views/win/fullscreen_handler.cc
[modify] https://crrev.com/854c089d7063043bc260865aeeb77dc6a1d1a793/ui/views/win/fullscreen_handler.h
[modify] https://crrev.com/854c089d7063043bc260865aeeb77dc6a1d1a793/ui/views/win/hwnd_message_handler.cc

Tested the issue on Windows-7 using chrome latest Beta M61-61.0.3163.71 by following steps mentioned in the original comment. Observed that Task bar is visible after switching into main profile from incognito window. and its working as expected. Hence adding TE-Verified label.

Please find the screen shot for reference.

Thank you!

Deleted: 758113.mp4 1.4 MB

	758113.mp4 1.4 MB View Download

marking the bug as fixed, given this been verified in Chrome Canary and Beta.