Try to improve toolbar separator coloration for themed browser windows.

chrome/browser/ui/libgtkui/gtk_ui.cc

Index: chrome/browser/ui/libgtkui/gtk_ui.cc
diff --git a/chrome/browser/ui/libgtkui/gtk_ui.cc b/chrome/browser/ui/libgtkui/gtk_ui.cc
index e9dd509fc7f73f39bdef69c19c997e41c19ccd41..d5b71d27e936dee0b033745d22554005e33be9c2 100644
--- a/chrome/browser/ui/libgtkui/gtk_ui.cc
+++ b/chrome/browser/ui/libgtkui/gtk_ui.cc
@@ -849,9 +849,6 @@ void GtkUi::LoadGtkValues() {
   // Separates entries in the downloads bar.
   colors_[ThemeProperties::COLOR_TOOLBAR_VERTICAL_SEPARATOR] =
       toolbar_separator_vertical;
-  // Separates the bookmark bar from the web content.
-  colors_[ThemeProperties::COLOR_DETACHED_BOOKMARK_BAR_SEPARATOR] =
-      toolbar_separator_horizontal;
 
   // These colors represent the border drawn around tabs and between
   // the tabstrip and toolbar.  It's unclear if the selectors used are