commit 45cb4bec233b0aaef44015efd5c8989fcb57155a
author Edin Kadric <edin@google.com> Wed Feb 27 16:01:08 2019
committer Commit Bot <commit-bot@chromium.org> Wed Feb 27 16:01:08 2019
tree 5462adcaaa06bf71f1d146d5fb5f46d497352245
parent 7c75e6932c53d6681a0015b5e7859f3d7531af39

Start EditableCombobox.

See associated bug for design doc and screen recording showing the new
control.

This CL gets us most of the way there, but there are still things to do
in subsequent CLs before we start using this control:
- I only tested this on Mac for now. I will add support for other OSes
later.
- The accessibility isn't quite right. It says to select with
control+option+space, but that doesn't work. I noticed that it doesn't
work for the regular Combobox either, so I will fix it for both in a
later CL.

Bug: 923660
Change-Id: I8e959e068af23491a842c4bc0fa9661cbd2869dd
Reviewed-on: https://chromium-review.googlesource.com/c/1466186
Commit-Queue: Edin Kadric <edinkadric@google.com>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Vasilii Sukhanov <vasilii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#636033}