setup: Fix arguments to setup without install

- When arguments are passed to --setup-no-install, use them correctly.

- Explicitly initialize member in constructor

- Minor indentation

plinth/__main__.py

@@ -304,8 +304,9 @@ def main():
     module_loader.load_modules()
     if arguments.setup is not False:
         run_setup_and_exit(arguments.setup)
+
     if arguments.setup_no_install is not False:
-        run_setup_and_exit(arguments.setup, allow_install=False)
+        run_setup_and_exit(arguments.setup_no_install, allow_install=False)
 
     if arguments.diagnose:
         run_diagnostics_and_exit()

plinth/setup.py

@@ -40,6 +40,7 @@ class Helper(object):
         self.current_operation = None
         self.is_finished = None
         self.exception = None
+        self.allow_install = True
 
     def run_in_thread(self):
         """Execute the setup process in a thread."""
@@ -98,6 +99,7 @@ class Helper(object):
             for package_name in package_names:
                 if not cache[package_name].is_installed:
                     raise PackageNotInstalledError(package_name)
+
             return
 
         logger.info('Running install for module - %s, packages - %s',