Omnibox: Add back vertical margin field trial

This CL is a partial revert of:

It adds back the vertical margin trial, but it no longer ties it to
kExperimentalUi. It's just set to 2 by default, to match the
pre-Refresh look as closely as possible.

This can be manually tested like this:


Bug: 931332
Change-Id: Ic590f736b141a20bb10ee1e4d4f688d18d68910f
Commit-Queue: Tommy Li <>
Reviewed-by: Justin Donnelly <>
Cr-Commit-Position: refs/heads/master@{#631521}
4 files changed