Merged r21992 from trunk to 5.0-stable (#36273).

git-svn-id: https://svn.redmine.org/redmine/branches/5.0-stable@21997 e93f8b46-1217-0410-a6f0-8f06a7374b81

config/initializers/zeitwerk.rb

@@ -2,6 +2,7 @@
 
 lib = Rails.root.join('lib/redmine')
 Rails.autoloaders.main.push_dir lib, namespace: Redmine
+Rails.application.config.watchable_dirs[lib] = [:rb]
 
 IGNORE_LIST = [
   'wiki_formatting/textile/redcloth3.rb',

lib/redmine/plugin_loader.rb

@@ -128,6 +128,7 @@ module Redmine
         engine_cfg.paths.add 'lib', eager_load: true
         engine_cfg.eager_load_paths.each do |dir|
           Rails.autoloaders.main.push_dir dir
+          Rails.application.config.watchable_dirs[dir] = [:rb]
         end
       end
     end