Good build: 52.0.2718.0 
Bad build:  52.0.2719.0 

Narrow bisect:
https://chromium.googlesource.com/chromium/src/+log/33b3cd875c5498abb636d472136b58606902b1be..4b13c18950dd930908dfc9ec83dccb980338e293?pretty=fuller&n=10000

Suspecting: r390131

Kindly review the attached screen-cast for reference.

Deleted: Actual_behavior.mp4 1.0 MB

Actual_behavior.mp4 1.0 MB Download

Deleted: Expected_behavior.mp4 842 KB

Expected_behavior.mp4 842 KB Download

Adding Release Block as this is a recent Regression. Please remove if not required.
Thank You.

I'm not sure whether we can control the "direction" of a 3D rotation.  I will check with the blink team in another ticket and see if this is possible:
https://bugs.chromium.org/p/chromium/issues/detail?id=610014

@Blink>CSS>3d: I filed a separate issue related to this behavior: https://bugs.chromium.org/p/chromium/issues/detail?id=610014

Could you please check it out and see if there's some way for 3D rotation animations to take the direction of the shortest path?

dchaubey@ - Friendly reminder, Could you please respond for the comment #4.

CL: https://codereview.chromium.org/1975723003/

A CL has been started.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/491764de4a847d265bb538b661e0f0eb078c7d3d

commit 491764de4a847d265bb538b661e0f0eb078c7d3d
Author: luoe <luoe@chromium.org>
Date: Wed May 18 22:19:54 2016

DevTools: fix janky transition in sensors panel

BUG= 609718 

Review-Url: https://codereview.chromium.org/1975723003
Cr-Commit-Position: refs/heads/master@{#394572}

[modify] https://crrev.com/491764de4a847d265bb538b661e0f0eb078c7d3d/third_party/WebKit/LayoutTests/inspector/components/geometry-expected.txt
[modify] https://crrev.com/491764de4a847d265bb538b661e0f0eb078c7d3d/third_party/WebKit/LayoutTests/inspector/components/geometry.html
[modify] https://crrev.com/491764de4a847d265bb538b661e0f0eb078c7d3d/third_party/WebKit/Source/devtools/front_end/common/Geometry.js
[modify] https://crrev.com/491764de4a847d265bb538b661e0f0eb078c7d3d/third_party/WebKit/Source/devtools/front_end/emulation/SensorsView.js
[modify] https://crrev.com/491764de4a847d265bb538b661e0f0eb078c7d3d/third_party/WebKit/Source/devtools/front_end/emulation/sensors.css

The landed CL didn't fix this:
https://codereview.chromium.org/1975723003/

But a new CL, in review, should:
https://codereview.chromium.org/1996013004/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/df711c5bbb88cd9be9853f011c6288fb4c8a0914

commit df711c5bbb88cd9be9853f011c6288fb4c8a0914
Author: luoe <luoe@chromium.org>
Date: Thu May 19 21:15:41 2016

DevTools: better SensorsView orientation fix

It's my fault for landing a patch that didn't actually fix the bug: https://codereview.chromium.org/1975723003/

This CL should 'actually' do the correct behavior, since the transform now does not depend on a WebKitCSSMatrix.

BUG= 609718 

Review-Url: https://codereview.chromium.org/1996013004
Cr-Commit-Position: refs/heads/master@{#394864}

[modify] https://crrev.com/df711c5bbb88cd9be9853f011c6288fb4c8a0914/third_party/WebKit/LayoutTests/inspector/components/geometry-expected.txt
[modify] https://crrev.com/df711c5bbb88cd9be9853f011c6288fb4c8a0914/third_party/WebKit/Source/devtools/front_end/common/Geometry.js
[modify] https://crrev.com/df711c5bbb88cd9be9853f011c6288fb4c8a0914/third_party/WebKit/Source/devtools/front_end/emulation/SensorsView.js

[Auto-generated comment by a script] We noticed that this issue is targeted for M-52; it appears the fix may have landed after branch point, meaning a merge might be required. Please confirm if a merge is required here - if so add Merge-Request-52 label, otherwise remove Merge-TBD label. Thanks.

[Bulk edit]

Our blockerbot script was offline; it was recently brought back online, and thus labeled many old issues (including this one) erroneously.  Removing Merge-TBD label since all milestones for this issue are already completed; no further work should be done.