Hide empty conversations in home view.

// FREEBIE

Signal/src/AppDelegate.m

@@ -171,6 +171,9 @@ static NSString *const kURLHostVerifyPrefix             = @"verify";
 
     NSString *lastLaunchedAppVersion = AppVersion.instance.lastAppVersion;
     NSString *lastCompletedLaunchAppVersion = AppVersion.instance.lastCompletedLaunchAppVersion;
+    // Every time we change a database view in such a way that might cause a delay on launch,
+    // we need to bump this constant.
+    //
     // We added a number of database views in v2.13.0.
     NSString *kLastVersionWithDatabaseViewChange = @"2.13.0";
     BOOL mayNeedUpgrade = ([TSAccountManager isRegistered] && lastLaunchedAppVersion