Bisected between 513360 and 513361.

Suspecting CL
https://chromium.googlesource.com/chromium/src/+/1eca7aba022c190ea02e34dbd4ae52a8f5f88bbc

Over to tapted@

If omnibox experiments break when Harmony is enabled, it's going to be on the omnibox team rather than the Harmony team to fix them -- we can support the primary UI, but not non-default experiments (due to bandwidth).

To jdonnelly to triage since I don't know who owns this experiment right now.

Also, confirming similar behavior on Windows.

We don't currently have plans to turn this option on for any users, so this isn't high priority to fix. (The option exists for PMs and designers to try it out and figure out how it fits with other design changes being contemplated.)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/10fd28c627d6bd70abb8388d9bbecea524bf0bc6

commit 10fd28c627d6bd70abb8388d9bbecea524bf0bc6
Author: Tommy C. Li <tommycli@chromium.org>
Date: Mon Dec 18 16:49:43 2017

Omnibox UI Experiments: Fix narrow-dropdown appearance for Harmony

Small fix to adjust the Omnibox suggestions dropdown for the new
Harmony (kSecondaryUiMd enabled) BubbleBorder.

Bug:  783778 
Change-Id: Id0b2a9e962aad098f46d53d1eedffad668639221
Reviewed-on: https://chromium-review.googlesource.com/831046
Reviewed-by: Justin Donnelly <jdonnelly@chromium.org>
Commit-Queue: Tommy Li <tommycli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#524727}
[modify] https://crrev.com/10fd28c627d6bd70abb8388d9bbecea524bf0bc6/chrome/browser/ui/views/omnibox/omnibox_popup_contents_view.cc

Tested the issue using #65.0.3298.3 on Linux Ubutnu 14.04, Win 10 as per the steps mentioned in comment #0.

Pre-condition
============
Enable #omnibox-ui-narrow-dropdown 

Note: 
1. This issue is not seen in Linux (Refer screenshot)
2. Issue is still reprodcuible in Win 10. (Refer screenshot)

@gcomanici: Please take a look at this issue.

Thanks!!

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Please ignore the above comment.

Tested the issue using #65.0.3299.0 on Linux Ubutnu 14.04, Win 10 as per the steps mentioned in comment #0. No chopping of text is seen.

Please find the screenshot's. Hence adding Verified labels.

Thanks!! 

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Although the problem is not as obvious as in the previous version (i.e. text is not chopped off) it still feels odd to have the margin too close to the text, especially when using letters such as g,y,p etc.

see attached image, based on using Chrome 65.0.3294.5 (Official Build) dev (64-bit) on Ubunti 14.04 

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Reopening per comment #9.

gcomanici: Can you still reproduce it on Canary 3299 or later? It may not have hit the build you are on.

Verified in 65.0.3300.0 (Ubuntu 14.04) and the issue is fixed.

Thanks!