[gtk/wip/jimmac/dropdown-styling] Adwaita: dropdown styling

[Jakub Steiner <jimmac src gnome org>]

commit b1cb1dafcd85c292856fb50a1fad2eb944669759
Author: Jakub Steiner <jimmac gmail com>
Date:   Mon Jun 15 15:18:04 2020 +0200

    Adwaita: dropdown styling
    
    - selected item color
    - offset dropdown form the parent control
    
    FIXME: don't center below the parent control, but left align to it
    FIXME: selected items are edge to egde
    FIXME: height of items in the list to match menus and popovers
    
    Fixes (eventually) https://gitlab.gnome.org/GNOME/gtk/-/issues/2846

 gtk/theme/Adwaita/_common.scss | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
---
diff --git a/gtk/theme/Adwaita/_common.scss b/gtk/theme/Adwaita/_common.scss
index d2ed052b06..266a587057 100644
--- a/gtk/theme/Adwaita/_common.scss
+++ b/gtk/theme/Adwaita/_common.scss
@@ -1171,8 +1171,25 @@ combobox {
 
     button.combo { @extend %button_basic_drop_active; }
   }
+
+  // newstyle
+  popover {
+   margin-top: 6px;
+
+   listview row {
+    //background-color: pink;
+
+      &:selected {
+        outline-color: $alt_focus_border_color;
+        color: $text-color;
+        background-color: $menu_selected_color;
+      }
+    }
+  }
 }
 
+
+
 // the combo is a composite widget so the way we do button linking doesn't
 // work, special case needed. See
 // https://bugzilla.gnome.org/show_bug.cgi?id=733979