GitLab

Creates animations for expanding and contracting the location bar/omnibox
using entirely UIViewPropertyAnimators.

The feature is behind a new flag that is disabled by default.

Real time video:
https://drive.google.com/open?id=0Byo6-Nuda2jgVE1yTjBPRU9ybjg

Slow Animations video:
https://drive.google.com/open?id=0Byo6-Nuda2jgR21YM3k0amEwUEE

Bug: 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet
Change-Id: Ib3a4f8f7aac9e72b674b881af2f463fabf76393a
Reviewed-on: https://chromium-review.googlesource.com/729839
Commit-Queue: Sergio Collazos <sczs@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512999}