[gtk/wip/jimmac/industrial-style-menuitems] WIP: Adwaita: revert edge-to-edge menuitems

[Jakub Steiner <jimmac src gnome org>]

commit f853c47e3659edd6c7e265dda9e3507b6129f649
Author: Jakub Steiner <jimmac gmail com>
Date:   Tue Nov 17 01:07:24 2020 +0100

    WIP: Adwaita: revert edge-to-edge menuitems
    
    - use the old Industrial style menuitems to make the design feel purposeful
    - adjust corners to have compatible border-radii of child elements
    - inclue sidebars and navigation sidebars to look consistent
      (plus the assistant sidebar)
    
    Implements https://gitlab.gnome.org/GNOME/gtk/-/issues/3366

 gtk/theme/Adwaita/_common.scss | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)
---
diff --git a/gtk/theme/Adwaita/_common.scss b/gtk/theme/Adwaita/_common.scss
index 68dd817677..ab13034d70 100644
--- a/gtk/theme/Adwaita/_common.scss
+++ b/gtk/theme/Adwaita/_common.scss
@@ -194,7 +194,10 @@ window.assistant {
 
   .sidebar > label { padding: 6px 12px; }
 
-  .sidebar > label.highlight { background-color: mix($bg_color, $fg_color, 80%); }
+  .sidebar > label.highlight {
+    background-color: $menu_selected_color;
+    border-radius: $menu_radius - 1;
+  }
 }
 
 %osd,
@@ -3389,6 +3392,7 @@ filechooserbutton:drop(active) {
  * Sidebar *
  ***********/
 .sidebar {
+  padding: $menu_radius;
   border-style: none;
   background-color: mix($bg_color, $base_color, 50%);
 
@@ -3441,11 +3445,14 @@ separator.sidebar {
  **********************/
 
 .navigation-sidebar {
+  padding: $menu_radius 0; //only vertical padding. horizontal row size would clip
 
   > row {
     // Needs overriding of the GtkListBoxRow padding
     min-height: 36px;
-    padding: 0px 8px;
+    padding: 0px 2px;
+    border-radius: $menu_radius - 1;
+    margin: 0 $menu_radius;
 
     // Using margins/padding directly in the SidebarRow
     // will make the animation of the new bookmark row jump
@@ -4177,7 +4184,7 @@ popover.menu {
   & > arrow,
   &.background > contents {
     background-color: $menu_color;
-    padding: 0;
+    padding: $menu_radius;
   }
 
   &.background separator {
@@ -4221,8 +4228,8 @@ popover.menu {
   modelbutton {
     min-height: 30px;
     min-width: 40px;
-    padding: $_menu-padding/6 $_menu-padding;
-    border-radius: 0;
+    padding: 0 $_menu-padding;
+    border-radius: $menu_radius - 1;
 
     &:selected {
       color: $text-color;
@@ -4262,7 +4269,7 @@ menubar {
   }
 
   & > item popover.menu.background > contents {
-    padding: 0;
+    padding: $menu_radius;
   }
   //nested submenus
   & > item popover.menu popover.menu {