Chrome Version:51.0.2672.0 (Official Build) b4fd57023ade2863e463d3380456968dca6c8bcf-refs/heads/master@{#380022} 64 bit
OS: Mac 

Pre-condition: 1. Select 'Material' option for 'Material design in the browser's top chrome'.
               2. Install any 2-3 extension such that extension icon should be present in browser action container. 
               3. Enable extension toolbar redesign.

What steps will reproduce the problem?
1. Launch chrome and try to drag the omnibox towards R.H.S with the help of dragger icon.
2. Observe.

Actual: Unable to drag the omnibox towards  R.H.S. (refer video)
Expected: Able to drag the omnibox  both the side with the help of dragger icon.

This is regression issue, broken in ‘M 51’ and below is narrow bisect:
https://chromium.googlesource.com/chromium/src/+log/bddee54521cae58e45f7ff92a2bf5819d7fe49de..554dd1c38b1c0ab60ff51189efce72774003a2e8?pretty=fuller&n=100

Suspecting: r379944 ?

Good build:51.0.2671.0 
Bad build:51.0.2672.0 

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

Deleted: Actual_drag.mov 1.8 MB

Actual_drag.mov 1.8 MB Download