Comment 2 for bug 1290876

StacktraceTop:
 get_user_label (user=0x95589f0, user=0x95589f0) at /build/buildd/indicator-session-12.10.5+14.04.20140214/src/service.c:288
 compare_users_by_label (ga=ga@entry=0x9555a10, gb=gb@entry=0x9555a14) at /build/buildd/indicator-session-12.10.5+14.04.20140214/src/service.c:457
 msort_with_tmp (p=p@entry=0xbfbb1528, b=b@entry=0x9555a10, n=n@entry=2) at /build/buildd/glib2.0-2.39.91/./glib/gqsort.c:93
 msort_with_tmp (p=p@entry=0xbfbb1528, b=0x9555a08, n=n@entry=4) at /build/buildd/glib2.0-2.39.91/./glib/gqsort.c:86
 msort_r (b=<optimized out>, n=<optimized out>, s=4, cmp=0x80565f0 <compare_users_by_label>, arg=0x0) at /build/buildd/glib2.0-2.39.91/./glib/gqsort.c:278