theme: Include both dark and light variant in resource

This will allow us to switch between the variants according to
the color-scheme setting.

https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/5545

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2324>

data/gnome-shell-theme.gresource.xml

@@ -9,7 +9,8 @@
     <file>checkbox-off-focused.svg</file>
     <file>checkbox-off-light.svg</file>
     <file>checkbox-off.svg</file>
-    <file>gnome-shell.css</file>
+    <file>gnome-shell-dark.css</file>
+    <file>gnome-shell-light.css</file>
     <file>gnome-shell-high-contrast.css</file>
     <file>gnome-shell-start.svg</file>
     <file>pad-osd.css</file>

data/theme/gnome-shell-light.scss

@@ -0,0 +1,6 @@
+$variant: 'light';
+
+@import "gnome-shell-sass/_colors"; //use gtk colors
+@import "gnome-shell-sass/_drawing";
+@import "gnome-shell-sass/_common";
+@import "gnome-shell-sass/_widgets";

data/theme/meson.build

@@ -1,6 +1,7 @@
 theme_sources = files([
   'gnome-shell-high-contrast.scss',
-  'gnome-shell.scss',
+  'gnome-shell-dark.scss',
+  'gnome-shell-light.scss',
   'gnome-shell-sass/_colors.scss',
   'gnome-shell-sass/_common.scss',
   'gnome-shell-sass/_drawing.scss',
@@ -43,7 +44,8 @@ theme_sources = files([
 
 stylesheets = [
   'gnome-shell-high-contrast.css',
-  'gnome-shell.css'
+  'gnome-shell-dark.css',
+  'gnome-shell-light.css',
 ]
 
 foreach stylesheet: stylesheets

js/ui/sessionMode.js

@@ -22,7 +22,7 @@ if (Config.HAVE_NETWORKMANAGER)
 const _modes = {
     'restrictive': {
         parentMode: null,
-        stylesheetName: 'gnome-shell.css',
+        stylesheetName: 'gnome-shell-dark.css',
         themeResourceName: 'gnome-shell-theme.gresource',
         hasOverview: false,
         showCalendarEvents: false,

meson/generate-stylesheets.py

@@ -6,7 +6,8 @@
 
 stylesheets = [
     'data/theme/gnome-shell-high-contrast.css',
-    'data/theme/gnome-shell.css'
+    'data/theme/gnome-shell-dark.css',
+    'data/theme/gnome-shell-light.css'
 ]
 
 sourceroot = os.environ.get('MESON_SOURCE_ROOT')