Initialize instance variable to remove warning

    actions.rb:34: warning: instance variable @in_group not initialized

railties/lib/rails/generators/actions.rb

@@ -4,6 +4,10 @@
 module Rails
   module Generators
     module Actions
+      def initialize(*) # :nodoc:
+        super
+        @in_group = nil
+      end
 
       # Adds an entry into Gemfile for the supplied gem.
       #