Merge commit 'd13d7b4566d551d027830f7dfc987ba3a8e2dd4f' into glitch-soc/merge-upstream

Conflicts are too numerous to list, but they are all caused by upstream's
theming changes and all have to do with the differences between upstream and
glitch-soc in the theming systems.

They were all manually resolved by adapting the relevant code.

app/controllers/application_controller.rb

@@ -11,18 +11,12 @@ class ApplicationController < ActionController::Base
   include CacheConcern
   include PreloadingConcern
   include DomainControlHelper
-  include ThemingConcern
   include DatabaseHelper
   include AuthorizedFetchHelper
   include SelfDestructHelper
 
   helper_method :current_account
   helper_method :current_session
-  helper_method :current_flavour
-  helper_method :current_skin
-  helper_method :current_theme
-  helper_method :color_scheme
-  helper_method :contrast
   helper_method :single_user_mode?
   helper_method :use_seamless_external_login?
   helper_method :sso_account_settings
@@ -176,25 +170,6 @@ class ApplicationController < ActionController::Base
     @current_session = SessionActivation.find_by(session_id: cookies.signed['_session_id']) if cookies.signed['_session_id'].present?
   end
 
-  def color_scheme
-    current = current_user&.setting_color_scheme
-    return current if current && current != 'auto'
-
-    return 'dark' if current_skin.include?('default') || current_skin.include?('contrast')
-    return 'light' if current_skin.include?('light')
-
-    'auto'
-  end
-
-  def contrast
-    current = current_user&.setting_contrast
-    return current if current && current != 'auto'
-
-    return 'high' if current_skin.include?('contrast')
-
-    'auto'
-  end
-
   def respond_with_error(code)
     respond_to do |format|
       format.any  { render "errors/#{code}", layout: 'error', status: code, formats: [:html] }

app/controllers/concerns/theming_concern.rb

@@ -1,24 +0,0 @@
-# frozen_string_literal: true
-
-module ThemingConcern
-  extend ActiveSupport::Concern
-
-  private
-
-  def current_flavour
-    @current_flavour ||= [current_user&.setting_flavour, Setting.flavour, 'glitch', 'vanilla'].find { |flavour| Themes.instance.flavours.include?(flavour) }
-  end
-
-  def current_skin
-    @current_skin ||= begin
-      skins = Themes.instance.skins_for(current_flavour)
-      [current_user&.setting_skin, Setting.skin, 'system', 'default'].find { |skin| skins.include?(skin) }
-    end
-  end
-
-  def current_theme
-    # NOTE: this is slightly different from upstream, as it's a derived value used
-    # for the sole purpose of pointing to the appropriate stylesheet pack
-    [current_flavour, current_skin]
-  end
-end