test-log test fails on some environ

[Mamoru TASAKA]

$ make check with libzeitguist 0.3.6 fails when rebuilt on some environ like:
http://koji.fedoraproject.org/koji/taskinfo?taskID=2932996
http://koji.fedoraproject.org/koji/getfile?taskID=2932996&name=build.log

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TEST: test-log... (pid=24876)
  /Zeitgeist/Log/InsertGetDelete:
GLib-GObject-CRITICAL **: g_object_unref: assertion `G_IS_OBJECT (object)' failed
aborting...
FAIL
GTester: last random seed: R02S599360e272ab08fc82438e1789deaecf
/bin/sh: line 1: 24795 Terminated gtester --verbose test-timerange test-timestamp test-symbols test-monitor test-log test-event test-datasource test-mimetypes
make[2]: *** [test] Error 143
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Perhaps when dbus is not running test-log test fails.
gdb log attached.

[Mamoru TASAKA (mtasaka)]

And workaround patch