The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f4acec7a4f8fe1e3e50785a7a601499c2f7619b5

commit f4acec7a4f8fe1e3e50785a7a601499c2f7619b5
Author: shrike <shrike@chromium.org>
Date: Thu Jun 16 16:24:12 2016

[Mac][Material Design] Adjust cutoff for detecting a "dark" theme.

Chrome looks at the whiteComponent of a theme's custom toolbar color to
decide if the theme is "dark." The line between ligth and dark is an
empirical value - this cl adjusts the cutoff in hopes of getting closer
to the right value.

R=tapted@chromium.org
BUG= 614806 , 617993 

Review-Url: https://codereview.chromium.org/2068243002
Cr-Commit-Position: refs/heads/master@{#400168}

[modify] https://crrev.com/f4acec7a4f8fe1e3e50785a7a601499c2f7619b5/chrome/browser/ui/cocoa/chrome_browser_window.mm

Tested this issue on Mac OS 10.11.5 using chrome latest canary M53-53.0.2770.0 and observed there was no dark theme in the custom toolbar in adding splendid theme.

shrike@ - Could you please confirm it from your end as well is this is the expected behavior of this issue, Attaching screen-cast for reference. It will be helpful to verify this issue from Chrome-TE end

Thanks!

Deleted: SplendidTheme.mp4 2.2 MB

	SplendidTheme.mp4 2.2 MB View Download

Your change meets the bar and is auto-approved for M52 (branch: 2743)

When Chrome Mac thinks a custom theme is dark it draws the toolbar control icons in white instead of gray, and uses black for the omnibox dropdown background. From your screencast the icons are gray and the dropdown is white. so it does not consider the Splendid theme as being dark, which is correct.

shrike@, Please have the CL merged to M52 branch by EOD today so that it gets picked up for Beta Promotion scheduled next week.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/75175ca5f6abba3c5d15cbbc1080ce8f5889a946

commit 75175ca5f6abba3c5d15cbbc1080ce8f5889a946
Author: Jayson Adams <shrike@chromium.org>
Date: Fri Jun 17 22:09:11 2016

[Mac][Material Design] Adjust cutoff for detecting a "dark" theme.

Chrome looks at the whiteComponent of a theme's custom toolbar color to
decide if the theme is "dark." The line between ligth and dark is an
empirical value - this cl adjusts the cutoff in hopes of getting closer
to the right value.

R=tapted@chromium.org
BUG= 614806 , 617993 

Review-Url: https://codereview.chromium.org/2068243002
Cr-Commit-Position: refs/heads/master@{#400168}
(cherry picked from commit f4acec7a4f8fe1e3e50785a7a601499c2f7619b5)

Review URL: https://codereview.chromium.org/2077743004 .

Cr-Commit-Position: refs/branch-heads/2743@{#384}
Cr-Branched-From: 2b3ae3b8090361f8af5a611712fc1a5ab2de53cb-refs/heads/master@{#394939}

[modify] https://crrev.com/75175ca5f6abba3c5d15cbbc1080ce8f5889a946/chrome/browser/ui/cocoa/chrome_browser_window.mm

Tested the issue on Mac 10.11.5 using 52.0.2743.49.Observed that icons are gray and the dropdown is white.
Please find attached screencast.

Marking it as TE-Verified.