The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b35763c08fbb775ce4748ac6167c83ea05e0c25e

commit b35763c08fbb775ce4748ac6167c83ea05e0c25e
Author: estade <estade@chromium.org>
Date: Sun Aug 21 02:26:40 2016

Reuse NativeThemeAuraDark for cros tray.

This means we'll stay in sync with other light-on-dark surfaces
(e.g. incognito) and we won't need to manually set label colors.

BUG= 638694 

Review-Url: https://codereview.chromium.org/2254933002
Cr-Commit-Position: refs/heads/master@{#413361}

[modify] https://crrev.com/b35763c08fbb775ce4748ac6167c83ea05e0c25e/ash/common/system/date/date_view.cc
[modify] https://crrev.com/b35763c08fbb775ce4748ac6167c83ea05e0c25e/ash/common/system/status_area_widget.cc
[modify] https://crrev.com/b35763c08fbb775ce4748ac6167c83ea05e0c25e/ash/common/system/status_area_widget.h
[modify] https://crrev.com/b35763c08fbb775ce4748ac6167c83ea05e0c25e/ash/common/system/tray/system_tray.cc
[modify] https://crrev.com/b35763c08fbb775ce4748ac6167c83ea05e0c25e/ash/common/system/tray/tray_utils.cc
[modify] https://crrev.com/b35763c08fbb775ce4748ac6167c83ea05e0c25e/ui/native_theme/native_theme_dark_aura.cc

marking fixed, although there might be some places we're still setting colors manually that are no longer necessary or can be moved into native theme dark