Inline html to report the plugin that implemented the feature.

changelog.html

@@ -65,6 +65,8 @@ Upcoming changes</a>
     Added UI component to show notification bar at the top of the page
   <li class="rfe">
     Users can configure search to be case insensitive.
+  <li class="rfe">
+    Inline help now reports the plugin that contributes the said feature.
 </ul>
 </div><!--=TRUNK-END=-->
 

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

@@ -24,6 +24,7 @@
 package hudson.model;
 
 import hudson.DescriptorExtensionList;
+import hudson.PluginWrapper;
 import hudson.RelativePath;
 import hudson.XmlFile;
 import hudson.BulkChange;
@@ -779,6 +780,16 @@ public abstract class Descriptor<T extends Describable<T>> implements Saveable {
         return new XmlFile(new File(Jenkins.getInstance().getRootDir(),getId()+".xml"));
     }
 
+    /**
+     * Returns the plugin in which this descriptor is defined.
+     *
+     * @return
+     *      null to indicate that this descriptor came from the core.
+     */
+    protected PluginWrapper getPlugin() {
+        return Jenkins.getInstance().getPluginManager().whichPlugin(clazz);
+    }
+
     /**
      * Serves <tt>help.html</tt> from the resource of {@link #clazz}.
      */
@@ -788,6 +799,14 @@ public abstract class Descriptor<T extends Describable<T>> implements Saveable {
 
         path = path.replace('/','-');
 
+        PluginWrapper pw = getPlugin();
+        if (pw!=null) {
+            rsp.setHeader("X-Plugin-Short-Name",pw.getShortName());
+            rsp.setHeader("X-Plugin-Long-Name",pw.getLongName());
+            rsp.setHeader("X-Plugin-From", Messages.Descriptor_From(
+                    pw.getLongName().replace("Hudson","Jenkins").replace("hudson","jenkins"), pw.getUrl()));
+        }
+
         for (Klass<?> c= getKlass(); c!=null; c=c.getSuperClass()) {
             RequestDispatcher rd = Stapler.getCurrentRequest().getView(c, "help"+path);
             if(rd!=null) {// template based help page

core/src/main/resources/hudson/model/Messages.properties

@@ -103,6 +103,9 @@ ComputerSet.NoSuchSlave=No such slave: {0}
 ComputerSet.SlaveAlreadyExists=Slave called ''{0}'' already exists
 ComputerSet.SpecifySlaveToCopy=Specify which slave to copy
 ComputerSet.DisplayName=nodes
+
+Descriptor.From=(from <a href="{1}">{0}</a>)
+
 Executor.NotAvailable=N/A
 
 ExternalJob.DisplayName=Monitor an external job

war/src/main/webapp/css/style.css

@@ -562,6 +562,11 @@ LABEL.attach-previous {
   margin-bottom: 1em;
 }
 
+.help .from-plugin {
+    text-align: right;
+    color: #666;
+}
+
 .help-area {
   /* this marker class is used by JavaScript to locate the area to display help text. */
 }

war/src/main/webapp/scripts/hudson-behavior.js

@@ -715,7 +715,8 @@ var hudsonRules = {
                 new Ajax.Request(this.getAttribute("helpURL"), {
                     method : 'get',
                     onSuccess : function(x) {
-                        div.innerHTML = x.responseText;
+                        var from = x.getResponseHeader("X-Plugin-From");
+                        div.innerHTML = x.responseText+(from?"<div class='from-plugin'>"+from+"</div>":"");
                         layoutUpdateCallback.call();
                     },
                     onFailure : function(x) {