Update documentation to reflect unsubscription with name.

activesupport/lib/active_support/notifications.rb

@@ -141,6 +141,11 @@ module ActiveSupport
   #
   #   ActiveSupport::Notifications.unsubscribe(subscriber)
   #
+  # You can also unsubscribe by passing the name of the subscriber object. Note
+  # that this will unsubscribe all subscriptions with the given name:
+  #
+  #   ActiveSupport::Notifications.unsubscribe("render")
+  #
   # == Default Queue
   #
   # Notifications ships with a queue implementation that consumes and publishes events
@@ -173,8 +178,8 @@ def subscribed(callback, *args, &block)
         unsubscribe(subscriber)
       end
 
-      def unsubscribe(args)
-        notifier.unsubscribe(args)
+      def unsubscribe(subscriber_or_name)
+        notifier.unsubscribe(subscriber_or_name)
       end
 
       def instrumenter

activesupport/lib/active_support/notifications/fanout.rb

@@ -25,9 +25,9 @@ def subscribe(pattern = nil, block = Proc.new)
         subscriber
       end
 
-      def unsubscribe(subscriber)
+      def unsubscribe(subscriber_or_name)
         synchronize do
-          @subscribers.reject! { |s| s.matches?(subscriber) }
+          @subscribers.reject! { |s| s.matches?(subscriber_or_name) }
           @listeners_for.clear
         end
       end