Revert "not using Hash.new for Eventable fixes the retain cycle until…

… this"

This reverts commit 98f6c18.

motion/reactor/eventable.rb

@@ -7,33 +7,28 @@ module Eventable
       # and be passed the arguments that are passed to
       # `trigger`.
       def on(event, &blk)
-        events_for_event(event).push blk
+        __events__[event].push blk
       end
 
       # When `event` is triggered, do not call the given
       # block any more
       def off(event, &blk)
-        __events__[event].delete_if { |b| b == blk } if __events__.key?(event)
+        __events__[event].delete_if { |b| b == blk }
         blk
       end
 
       # Trigger an event
       def trigger(event, *args)
-        blks = events_for_event(event).clone
+        blks = __events__[event].clone
         blks.map do |blk|
           blk.call(*args)
         end
       end
 
       private
 
-      def events_for_event(event)
-        __events__[event] ||= []
-        __events__[event]
-      end
-
       def __events__
-        @__events__ ||= {}
+        @__events__ ||= Hash.new { |h,k| h[k] = [] }
       end
     end
   end