TIMOB-16889: fix Android activity lifecycle events

See explanation and test app in JIRA issue:
https://jira.appcelerator.org/browse/TIMOB-16889
Sync calls in the activity's lifecycle functions may cause some other issues. That's why we remove the sync events (https://jira.appcelerator.org/browse/TIMOB-16279). So can you specify in which case you have to use sync calls? Otherwise, async calls should be used.