Use the right instrumentation name

The pattern is event.component

Closes #11769

Conflicts:
	railties/CHANGELOG.md

railties/CHANGELOG.md

@@ -1,3 +1,7 @@
+*   Fix the event name of action_dispatch requests.
+
+    *Rafael Mendonça França*
+
 *   Make `config.log_level` work with custom loggers.
 
     *Max Shytikov*

railties/lib/rails/rack/logger.rb

@@ -33,7 +33,7 @@ module Rails
           logger.debug ''
         end
 
-        @instrumenter.start 'action_dispatch.request', request: request
+        @instrumenter.start 'request.action_dispatch', request: request
         logger.info started_request_message(request)
         resp = @app.call(env)
         resp[2] = ::Rack::BodyProxy.new(resp[2]) { finish(request) }
@@ -70,7 +70,7 @@ module Rails
       private
 
       def finish(request)
-        @instrumenter.finish 'action_dispatch.request', request: request
+        @instrumenter.finish 'request.action_dispatch', request: request
       end
 
       def development?

railties/test/rack_logger_test.rb

@@ -38,7 +38,7 @@ module Rails
       def setup
         @subscriber = Subscriber.new
         @notifier = ActiveSupport::Notifications.notifier
-        notifier.subscribe 'action_dispatch.request', subscriber
+        notifier.subscribe 'request.action_dispatch', subscriber
       end
 
       def teardown