Fix method name to register custom event types in plugins

Change-Id: I6dd2035de403e3d6ce1d7c78634a3a0ffd8feff1
diff --git a/Documentation/dev-plugins.txt b/Documentation/dev-plugins.txt
index 64cae2d..a80b4b5 100644
--- a/Documentation/dev-plugins.txt
+++ b/Documentation/dev-plugins.txt
@@ -474,9 +474,9 @@
 ----
 
 Plugins which define new Events should register them via the
-`com.google.gerrit.server.events.EventTypes.registerClass()`
-method. This will make the EventType known to the system.
-Deserializing events with the
+`com.google.gerrit.server.events.EventTypes.register()` method.
+This will make the EventType known to the system. Deserializing
+events with the
 `com.google.gerrit.server.events.EventDeserializer` class requires
 that the event be registered in EventTypes.