GitLab

This CL:
- Adds tests for the status bar color in overview mode.
- Adds @Feature({"StatusBar"}) to all status bar tests
- Adds documentation for why ThemeTestUtils#assertStatusBarColor() is
L+

BUG=1015627

Change-Id: If17b35cad970942add9525229da3275ac31b6adb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2069501
Commit-Queue: Peter Kotwicz <pkotwicz@chromium.org>
Reviewed-by: Theresa  <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#744149}