Try to improve toolbar separator coloration for themed browser windows.

chrome/browser/ui/views/frame/browser_view.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/views/frame/browser_view.h"
 
 #include <stdint.h>
 
 #include <algorithm>
 #include <memory>
@@ skipping 203 matching lines @@
   // In detached mode, the bar is meant to overlap with |contents_container_|.
   // The detached background color may be partially transparent, but the layer
   // for |view| must be painted opaquely to avoid subpixel anti-aliasing
   // artifacts, so we recreate the contents container base color here.
   canvas->FillRect(fill_rect,
                    tp->GetColor(ThemeProperties::COLOR_CONTROL_BACKGROUND));
   canvas->FillRect(
       fill_rect,
       tp->GetColor(ThemeProperties::COLOR_DETACHED_BOOKMARK_BAR_BACKGROUND));
 
-  // Draw the separators above and below bookmark bar;
-  // if animating, these are fading in/out.
-  SkColor separator_color =
-      tp->GetColor(ThemeProperties::COLOR_DETACHED_BOOKMARK_BAR_SEPARATOR);
-
-  // For the bottom separator, increase the luminance. Either double it or halve
-  // the distance to 1.0, whichever is less of a difference.
-  color_utils::HSL hsl;
-  color_utils::SkColorToHSL(separator_color, &hsl);
-  hsl.l = std::min((hsl.l + 1) / 2, hsl.l * 2);
+  // Draw the separator below the detached bookmark bar.
   BrowserView::Paint1pxHorizontalLine(
-      canvas, color_utils::HSLToSkColor(hsl, SK_AlphaOPAQUE),
+      canvas,
+      tp->GetColor(ThemeProperties::COLOR_DETACHED_BOOKMARK_BAR_SEPARATOR),
       view->GetLocalBounds(), true);
 }
 
 // Paints the background (including the theme image behind content area) for
 // the Bookmarks Bar when it is attached to the Toolbar into |bounds|.
 // |background_origin| is the origin to use for painting the theme image.
 void PaintBackgroundAttachedMode(gfx::Canvas* canvas,
                                  const ui::ThemeProvider* theme_provider,
                                  const gfx::Rect& bounds,
                                  const gfx::Point& background_origin) {
@@ skipping 2398 matching lines @@
 }
 
 extensions::ActiveTabPermissionGranter*
 BrowserView::GetActiveTabPermissionGranter() {
   content::WebContents* web_contents = GetActiveWebContents();
   if (!web_contents)
     return nullptr;
   return extensions::TabHelper::FromWebContents(web_contents)
       ->active_tab_permission_granter();
 }