GitLab

UnifiedSystemTray can be expanded or collapsed by touch gestures, but
it's confusing that it's also possible when a detailed view is shown.

TEST=manual
BUG=none

Change-Id: Iac81bbb645036560aa01c43bd86de735e3e904dc
Reviewed-on: https://chromium-review.googlesource.com/c/1352088
Commit-Queue: Tetsui Ohkubo <tetsui@chromium.org>
Reviewed-by: Manu Cornet <manucornet@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612080}