[JENKINS-59679] Use plugin URL from the update site rather than the manifest (#4273)

* Use plugin URL from the update site rather than the manifest

* Avoid Mockito when not needed

* Resolve plugin URL from multiple update sites

core/src/main/java/hudson/PluginWrapper.java

@@ -521,20 +521,30 @@ public class PluginWrapper implements Comparable<PluginWrapper>, ModelObject {
      */
     @Exported
     public String getUrl() {
-        // first look for the manifest entry. This is new in maven-hpi-plugin 1.30
+        // first look in update center metadata
+        List<UpdateSite.Plugin> siteMetadataList = getInfoFromAllSites();
+        String firstSiteUrl = null;
+        if (!siteMetadataList.isEmpty()) {
+        	firstSiteUrl = siteMetadataList.get(0).wiki;
+            if (allUrlsMatch(firstSiteUrl, siteMetadataList)) {
+                return firstSiteUrl;
+            }
+        }
+
+        // if update sites give different / empty results,
+        // use manifest (since maven-hpi-plugin 1.30)
         String url = manifest.getMainAttributes().getValue("Url");
-        if(url!=null)      return url;
-
-        // fallback to update center metadata
-        UpdateSite.Plugin ui = getInfo();
-        if(ui!=null)    return ui.wiki;
-
-        return null;
+        if (url != null) {
+        	return url;
+        }
+        return firstSiteUrl;
     }
-    
-    
 
-    @Override
+    private boolean allUrlsMatch(String url, List<UpdateSite.Plugin> uiList) {
+        return uiList.stream().allMatch(k -> k.wiki != null && k.wiki.equals(url));
+    }
+
+	@Override
     public String toString() {
         return "Plugin:" + getShortName();
     }
@@ -972,6 +982,11 @@ public class PluginWrapper implements Comparable<PluginWrapper>, ModelObject {
         return uc.getPlugin(getShortName());
     }
 
+    private List<UpdateSite.Plugin> getInfoFromAllSites() {
+        UpdateCenter uc = Jenkins.get().getUpdateCenter();
+        return uc.getPluginFromAllSites(getShortName(), getVersionNumber());
+    }
+
     /**
      * Returns true if this plugin has update in the update center.
      *