Screenshot of PS1 here: https://codereview.chromium.org/2854263002

Deleted: Screenshot from 2017-05-02 16:07:36.png 159 KB

	Screenshot from 2017-05-02 16:07:36.png 159 KB View Download

FYI, this is the first step in a series of experimental suggest UI changes we'll be making. We'll be sharing a plan soon that describes the changes and our plans for evaluating them.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2bb95c4284a7126fe819f7ead0cee521cab7ca87

commit 2bb95c4284a7126fe819f7ead0cee521cab7ca87
Author: tommycli <tommycli@chromium.org>
Date: Mon May 08 18:07:02 2017

Omnibox UI Experiments: Add vertical margin variations to about:flags

This CL implements it on Views only. There will be a followup to do
the variation on Mac.

BUG= 717777 

Review-Url: https://codereview.chromium.org/2854263002
Cr-Commit-Position: refs/heads/master@{#470050}

[modify] https://crrev.com/2bb95c4284a7126fe819f7ead0cee521cab7ca87/chrome/browser/about_flags.cc
[modify] https://crrev.com/2bb95c4284a7126fe819f7ead0cee521cab7ca87/chrome/browser/flag_descriptions.cc
[modify] https://crrev.com/2bb95c4284a7126fe819f7ead0cee521cab7ca87/chrome/browser/flag_descriptions.h
[modify] https://crrev.com/2bb95c4284a7126fe819f7ead0cee521cab7ca87/chrome/browser/ui/views/omnibox/omnibox_result_view.cc
[modify] https://crrev.com/2bb95c4284a7126fe819f7ead0cee521cab7ca87/components/omnibox/browser/omnibox_field_trial.cc
[modify] https://crrev.com/2bb95c4284a7126fe819f7ead0cee521cab7ca87/components/omnibox/browser/omnibox_field_trial.h
[modify] https://crrev.com/2bb95c4284a7126fe819f7ead0cee521cab7ca87/tools/metrics/histograms/enums.xml

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6c821888667803cb403d104523637008200b5161

commit 6c821888667803cb403d104523637008200b5161
Author: tommycli <tommycli@chromium.org>
Date: Wed May 10 22:20:48 2017

Omnibox UI Experiments: Clean up naming for Vertical Margin

Previous naming was a bit convoluted because we thought we would
coalesce all UI experiments into a single base::Feature.

New thinking is that it's cleanest to make a separate base::Feature for
each UI experiment.

BUG= 717777 

Review-Url: https://codereview.chromium.org/2874593002
Cr-Commit-Position: refs/heads/master@{#470729}

[modify] https://crrev.com/6c821888667803cb403d104523637008200b5161/chrome/browser/about_flags.cc
[modify] https://crrev.com/6c821888667803cb403d104523637008200b5161/chrome/browser/ui/views/omnibox/omnibox_result_view.cc
[modify] https://crrev.com/6c821888667803cb403d104523637008200b5161/components/omnibox/browser/omnibox_field_trial.cc
[modify] https://crrev.com/6c821888667803cb403d104523637008200b5161/components/omnibox/browser/omnibox_field_trial.h
[modify] https://crrev.com/6c821888667803cb403d104523637008200b5161/tools/metrics/histograms/enums.xml

Adding screenshot of Cocoa implementation: 

Deleted: Screen Shot 2017-05-10 at 4.22.15 PM.png 270 KB

	Screen Shot 2017-05-10 at 4.22.15 PM.png 270 KB View Download

Engineering doc for reference: https://docs.google.com/a/google.com/document/d/1krPjee88Wj_sIXE1rhTyPMT0-Chi-MdfHwo8sbl5pno/edit?usp=sharing

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ea05207e94618c286f12bbf97f5f65ecc552d663

commit ea05207e94618c286f12bbf97f5f65ecc552d663
Author: tommycli <tommycli@chromium.org>
Date: Mon May 15 17:34:24 2017

Omnibox UI Experiments: Port vertical margin experiment to Cocoa.

Ports the Omnibox UI vertical margin experiment to Cocoa.

See: https://codereview.chromium.org/2854263002/

BUG= 717777 

Review-Url: https://codereview.chromium.org/2874923002
Cr-Commit-Position: refs/heads/master@{#471818}

[modify] https://crrev.com/ea05207e94618c286f12bbf97f5f65ecc552d663/chrome/browser/ui/cocoa/omnibox/omnibox_popup_cell.h
[modify] https://crrev.com/ea05207e94618c286f12bbf97f5f65ecc552d663/chrome/browser/ui/cocoa/omnibox/omnibox_popup_cell.mm
[modify] https://crrev.com/ea05207e94618c286f12bbf97f5f65ecc552d663/chrome/browser/ui/cocoa/omnibox/omnibox_popup_matrix.mm

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0705a49d8d56f04b6178d0d8dceed9c83d2105fb

commit 0705a49d8d56f04b6178d0d8dceed9c83d2105fb
Author: tommycli <tommycli@chromium.org>
Date: Thu Jun 08 18:00:42 2017

Omnibox UI Experiments: Make vertical margin options increments of 2px

Increments of 4px were too much -- and 16px and 20px were comically
large.

BUG= 717777 

Review-Url: https://codereview.chromium.org/2931653002
Cr-Commit-Position: refs/heads/master@{#478021}

[modify] https://crrev.com/0705a49d8d56f04b6178d0d8dceed9c83d2105fb/chrome/browser/about_flags.cc

Verified this issue on Windows 10, Ubuntu 14.04 and Mac 10.12.5 with chrome #61.0.3128.0

As per comment comment #9, observed under "omnibox UI Vertical Margin" flag  have seen increments in 2px, hence adding TE-Verified labels.

Attaching the screen-cast for reference.

Deleted: 717777.mp4 524 KB

	717777.mp4 524 KB View Download