[FIXED JENKINS-34882] Honor non-default update sites in setup wizard (#2469)

* [FIXED JENKINS-34882] Honor non-default update sites during install

* Fix pluginSetupWizard tests

* Fix lint

core/src/main/resources/jenkins/install/SetupWizard/wizard-ui.jelly

 <?jelly escape-by-default='true'?>
 <j:jelly xmlns:j="jelly:core" xmlns:f="/lib/form" xmlns:st="jelly:stapler">
   <script type="text/javascript">
+    <j:getStatic var="defaultUpdateSiteId" className="hudson.model.UpdateCenter" field="ID_DEFAULT"/>
+    var defaultUpdateSiteId = '${defaultUpdateSiteId ? defaultUpdateSiteId.replace("'", "") : "default"}';
     var setupWizardExtensions = [];
     var onSetupWizardInitialized = function(extension) {
       setupWizardExtensions.push(extension);

war/src/main/js/pluginSetupWizardGui.js

@@ -1030,10 +1030,9 @@ var createPluginSetupWizard = function(appendTarget) {
 	}
 	
 	var showInitialSetupWizard = function() {
-		// check for connectivity
-		//TODO: make the Update Center ID configurable
-		var siteId = 'default';
-		jenkins.testConnectivity(siteId, handleGenericError(function(isConnected, isFatal, errorMessage) {
+		// check for connectivity to the configured default update site
+		/* globals defaultUpdateSiteId: true */
+		jenkins.testConnectivity(defaultUpdateSiteId, handleGenericError(function(isConnected, isFatal, errorMessage) {
 			if(!isConnected) {
 				if (isFatal) { // We cannot continue, show error
 					setPanel(errorPanel, { errorMessage: 'Default update site connectivity check failed with fatal error: ' + errorMessage + '. If you see this issue for the custom Jenkins WAR bundle, consider setting the correct value of the hudson.model.UpdateCenter.defaultUpdateSiteId system property (requires Jenkins restart). Otherwise please create a bug in Jenkins JIRA.' });

war/src/test/js/pluginSetupWizard-spec.js

@@ -9,6 +9,9 @@ var getJQuery = function() {
     return $;
 };
 
+/* globals defaultUpdateSiteId: true */
+defaultUpdateSiteId = 'default';
+
 // Iterates through all responses until the end and returns the last response repeatedly
 var LastResponse = function(responses) {
     var counter = 0;