GitLab

Both GoogleRed600 and GoogleRed700 were in use. Consolidate on 600.
Both GoogleGreen600 and GoogleGreen700 were in use. Consolidate on 700.

Change some code that hardcodes these colors to instead consult the
NativeTheme.

Bug: 990402
Change-Id: Ie99d58859bac22df7f71134650ab094ce8c1a94a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1733094
Commit-Queue: Evan Stade <estade@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Cr-Commit-Position: refs/heads/master@{#686237}