added a callback for configuration changes in Nodes.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@34817 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/model/Hudson.java

@@ -1096,6 +1096,8 @@ public final class Hudson extends Node implements ItemGroup<TopLevelItem>, Stapl
             }
         }
         getQueue().scheduleMaintenance();
+        for (ComputerListener cl : ComputerListener.all())
+            cl.onConfigurationChange();
     }
 
     private void updateComputer(Node n, Map<String,Computer> byNameMap, Set<Computer> used) {

core/src/main/java/hudson/slaves/ComputerListener.java

@@ -123,6 +123,12 @@ public abstract class ComputerListener implements ExtensionPoint {
      */
     public void onOffline(Computer c) {}
 
+    /**
+     * Called when configuration of the node was changed, a node is added/removed, etc.
+     * @since 1.377
+     */
+    public void onConfigurationChange() {}
+
     /**
      * Registers this {@link ComputerListener} so that it will start receiving events.
      *