installers fixed: do not instantiate ProgressWindow in headless environment

platform/platform-impl/src/com/intellij/openapi/application/impl/ApplicationImpl.java

@@ -594,6 +594,7 @@ public class ApplicationImpl extends PlatformComponentManagerImpl implements App
     boolean writeAccessAllowed = isInsideWriteActionEDTOnly();
     if (writeAccessAllowed // Disallow running process in separate thread from under write action.
                            // The thread will deadlock trying to get read action otherwise.
+        || isHeadlessEnvironment() && !isUnitTestMode()
       ) {
       LOG.debug("Starting process with progress from within write action makes no sense");
       try {