DbStateException when getting status for message in invisible group

I got this exception when opening a conversation with a fake test data contact.

The likely cause is that the contact has never sent any client version updates, so the contact group is invisible and therefore no status rows exist. It's possible for real contacts' contact groups to be invisible too, so we need to check for this instead of throwing an exception.

org.briarproject.bramble.api.db.DbException: org.briarproject.bramble.db.DbStateException
                                                                                                at org.briarproject.bramble.db.JdbcDatabase.getMessageStatus(JdbcDatabase.java:1765)
                                                                                                at org.briarproject.bramble.db.JdbcDatabase.getMessageStatus(JdbcDatabase.java:73)
                                                                                                at org.briarproject.bramble.db.DatabaseComponentImpl.getMessageStatus(DatabaseComponentImpl.java:574)
                                                                                                at org.briarproject.briar.introduction.IntroductionManagerImpl.getIntroductionMessages(IntroductionManagerImpl.java:416)
                                                                                                at org.briarproject.briar.android.contact.ConversationActivity.lambda$loadMessages$3$ConversationActivity(ConversationActivity.java:347)
                                                                                                at org.briarproject.briar.android.contact.ConversationActivity$$Lambda$3.run(Unknown Source)
                                                                                                at org.briarproject.briar.android.controller.DbControllerImpl.lambda$runOnDbThread$0$DbControllerImpl(DbControllerImpl.java:35)
                                                                                                at org.briarproject.briar.android.controller.DbControllerImpl$$Lambda$0.run(Unknown Source)
                                                                                                at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
                                                                                                at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
                                                                                                at java.lang.Thread.run(Thread.java:818)