Merge pull request #491 from ndeloof/JENKINS-13909

[JENKINS-13909] don't keep legacy *.hpi when uploading a plugin

core/src/main/java/hudson/PluginManager.java

@@ -706,6 +706,7 @@ public abstract class PluginManager extends AbstractModelObject {
                 throw new Failure(hudson.model.Messages.Hudson_NotAPlugin(fileName));
             }
             final String baseName = FilenameUtils.getBaseName(fileName);
+            new File(rootDir, baseName + ".hpi").delete(); // don't keep confusing legacy *.hpi
             fileItem.write(new File(rootDir, baseName + ".jpi")); // rename all new plugins to *.jpi
             fileItem.delete();