split off Plugin.configure() integration into GlobalConfiguration pluggability point

core/src/main/java/jenkins/model/GlobalPluginConfiguration.java

+package jenkins.model;
+
+import hudson.Extension;
+import hudson.Plugin;
+import hudson.StructuredForm;
+import net.sf.json.JSONObject;
+import org.kohsuke.stapler.StaplerRequest;
+
+import javax.servlet.ServletException;
+import java.io.IOException;
+
+/**
+ * Include config.jelly defined for {@link Plugin}s.
+ *
+ * <p>
+ * This object just acts as a proxy to configure {@link Jenkins#clouds}
+ *
+ * @author Kohsuke Kawaguchi
+ */
+@Extension(ordinal=100) // historically this was placed above general configuration from arbitrary descriptors
+public class GlobalPluginConfiguration  extends GlobalConfiguration {
+    @Override
+    public boolean configure(StaplerRequest req, JSONObject json) throws FormException {
+        try {
+            for( JSONObject o : StructuredForm.toList(json, "plugin"))
+                Jenkins.getInstance().pluginManager.getPlugin(o.getString("name")).getPlugin().configure(req, o);
+            return true;
+        } catch (IOException e) {
+            throw new FormException(e,"plugin");
+        } catch (ServletException e) {
+            throw new FormException(e,"plugin");
+        }
+    }
+}

core/src/main/java/jenkins/model/Jenkins.java

@@ -2516,9 +2516,6 @@ public class Jenkins extends AbstractCIBase implements ModifiableItemGroup<TopLe
             for( Descriptor<?> d : Functions.getSortedDescriptorsForGlobalConfig() )
                 result &= configureDescriptor(req,json,d);
 
-            for( JSONObject o : StructuredForm.toList(json,"plugin"))
-                pluginManager.getPlugin(o.getString("name")).getPlugin().configure(req, o);
-
             JSONObject np = json.getJSONObject("globalNodeProperties");
             if (!np.isNullObject()) {
                 globalNodeProperties.rebuild(req, np, NodeProperty.for_(this));

core/src/main/resources/jenkins/model/GlobalPluginConfiguration/config.groovy

+package jenkins.model.GlobalPluginConfiguration
+
+import hudson.Functions
+
+def f=namespace(lib.FormTagLib)
+
+// list config pages from plugins, if any
+app.pluginManager.plugins.each { p ->
+    if (Functions.hasView(p.plugin,"config.jelly")) {
+        f.rowSet(name:"plugin") {
+            f.invisibleEntry {
+                input (type:"hidden", name:"name", value:p.shortName)
+            }
+            include(p.plugin, "config")
+        }
+    }
+}

core/src/main/resources/jenkins/model/Jenkins/configure.jelly

@@ -166,18 +166,6 @@ THE SOFTWARE.
                           descriptors="${h.getNodePropertyDescriptors(it.class)}"
                           instances="${it.globalNodeProperties}" />
 
-      <!-- list config pages from plugins, if any -->
-      <j:forEach var="p" items="${it.pluginManager.plugins}">
-        <j:if test="${h.hasView(p.plugin,'config.jelly')}">
-          <f:rowSet name="plugin">
-            <f:invisibleEntry>
-              <input type="hidden" name="name" value="${p.shortName}"/>
-            </f:invisibleEntry>
-            <st:include page="config.jelly" it="${p.plugin}" optional="true"/>
-          </f:rowSet>
-        </j:if>
-      </j:forEach>
-
       <!-- global configuration from everyone -->
       <j:forEach var="descriptor" items="${h.getSortedDescriptorsForGlobalConfig()}">
         <j:set var="instance" value="${descriptor}" /><!-- this makes the <f:textbox field=.../> work -->