Fixed build file for service_only bootstrap
Fixed build file for service_only bootstrap

The build.py file expects the window arg to be set, however, when building with a service_only bootstrap, this variable is not set. This results in an error when building the private.mp3 resource.

rnixx/python-for-android,rnixx/python-for-android,germn/python-for-android,kivy/python-for-android,kivy/python-for-android,kronenpj/python-for-android,PKRoma/python-for-android,PKRoma/python-for-android,germn/python-for-android,kronenpj/python-for-android,PKRoma/python-for-android,germn/python-for-android,kivy/python-for-android,PKRoma/python-for-android,kronenpj/python-for-android,kronenpj/python-for-android,rnixx/python-for-android,germn/python-for-android,rnixx/python-for-android,kivy/python-for-android,PKRoma/python-for-android,rnixx/python-for-android,rnixx/python-for-android,kronenpj/python-for-android,germn/python-for-android,germn/python-for-android,kivy/python-for-android