MaharaDroid doesn't work when user doesn't have any tags

[GoogleCodeExporter]

Report on https://bugs.launchpad.net/mahara/+bug/1268786 :

This is an issue as a fresh user has no tags, workaround is to make a single 
tag, which then fixes it, error log below

 [Tue Jan 14 11:07:18 2014] [error] [client 10.22.33.88] [WAR] 88 (api/mobile/sync.php:77) Invalid argument supplied for foreach()
 [Tue Jan 14 11:07:18 2014] [error] [client 10.22.33.88] Call stack (most recent first):
 [Tue Jan 14 11:07:18 2014] [error] [client 10.22.33.88] * log_message("Invalid argument supplied for foreach()", 8, true, true, "/home/demo/code/mahara/htdocs/api/mobile/sync.php", 77) at /home/demo/code/mahara/htdocs/lib/errors.php:430
 [Tue Jan 14 11:07:18 2014] [error] [client 10.22.33.88] * error(2, "Invalid argument supplied for foreach()", "/home/demo/code/mahara/htdocs/api/mobile/sync.php", 77, array(size 59)) at /home/demo/code/mahara/htdocs/api/mobile/sync.php:77
 [Tue Jan 14 11:07:18 2014] [error] [client 10.22.33.88]

Original issue reported on code.google.com by [email protected] on 24 Aug 2014 at 4:10