Gtk3: Fix separator color on Gtk3.20

chrome/browser/ui/libgtkui/native_theme_gtk3.cc

 // Copyright 2016 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/libgtkui/native_theme_gtk3.h"
 
 #include <gtk/gtk.h>
 
 #include "chrome/browser/ui/libgtkui/chrome_gtk_frame.h"
 #include "chrome/browser/ui/libgtkui/chrome_gtk_menu_subclasses.h"
@@ skipping 83 matching lines @@
       return GetFgColor(
           "GtkMenu#menu GtkMenuItem#menuitem:disabled GtkLabel#label");
     case ui::NativeTheme::kColorId_MenuItemSubtitleColor:
       return GetFgColor(
           "GtkMenu#menu GtkMenuItem#menuitem GtkLabel#label.accelerator");
     case ui::NativeTheme::kColorId_MenuSeparatorColor:
     // MenuButton borders are used the same way as menu separators in Chrome.
     case ui::NativeTheme::kColorId_EnabledMenuButtonBorderColor:
     case ui::NativeTheme::kColorId_FocusedMenuButtonBorderColor:
     case ui::NativeTheme::kColorId_HoverMenuButtonBorderColor:
-      return GetFgColor("GtkMenu#menu GtkMenuItem#menuitem.separator:disabled");
+      if (GtkVersionCheck(3, 20))
+        return GetBgColor("GtkMenu#menu GtkSeparator#separator");
+      else
+        return GetFgColor("GtkMenu#menu GtkMenuItem#menuitem.separator");
 
     // Label
     case ui::NativeTheme::kColorId_LabelEnabledColor:
       return GetFgColor("GtkLabel#label");
     case ui::NativeTheme::kColorId_LabelDisabledColor:
       return GetFgColor("GtkLabel#label:disabled");
     case ui::NativeTheme::kColorId_LabelTextSelectionColor:
       return GetFgColor("GtkLabel#label #selection:selected");
     case ui::NativeTheme::kColorId_LabelTextSelectionBackgroundFocused:
       return GetBgColor("GtkLabel#label #selection:selected");
@@ skipping 15 matching lines @@
         gdk_color_free(color);
         return ret_color;
       } else {
         // Default color comes from gtklinkbutton.c.
         return SkColorSetRGB(0x00, 0x00, 0xEE);
       }
     }
 
     // Separator
     case ui::NativeTheme::kColorId_SeparatorColor:
-      return GetFgColor("GtkSeparator#separator.horizontal");
+      if (GtkVersionCheck(3, 20))
+        return GetBgColor("GtkSeparator#separator.horizontal");
+      else
+        return GetFgColor("GtkSeparator#separator.horizontal");
 
     // Button
     case ui::NativeTheme::kColorId_ButtonEnabledColor:
       return GetFgColor("GtkButton#button.text-button GtkLabel#label");
     case ui::NativeTheme::kColorId_ButtonDisabledColor:
       return GetFgColor("GtkButton#button.text-button:disabled GtkLabel#label");
     case ui::NativeTheme::kColorId_ButtonHoverColor:
       return GetFgColor("GtkButton#button.text-button:hover GtkLabel#label");
     case ui::NativeTheme::kColorId_ButtonPressedShade:
       return SK_ColorTRANSPARENT;
@@ skipping 198 matching lines @@
 void NativeThemeGtk3::PaintMenuItemBackground(
     SkCanvas* canvas,
     State state,
     const gfx::Rect& rect,
     const MenuItemExtraParams& menu_item) const {
   PaintWidget(canvas, rect, "GtkMenu#menu GtkMenuItem#menuitem",
               StateToStateFlags(state));
 }
 
 }  // namespace libgtkui