Adds checking dbus error messages
It can't check error messages properly because dbus error message has a
space before org.tizen.bla. Besides, the messages are little difference
between sound-server and pulseaudio.
e.g)
a error message from sound-server(g_dbus api)
GDBus.Error:org.tizen.multimedia.audio.Internal: failed
a error message from pulseaudio(dbus api)
GDBus.Error:org.freedesktop.DBus.Error.Failed: org.tizen.multimedia.audio.Internal
[Version] 0.12.70
[Issue Type] Bug
Change-Id: I1f0ba391dd3645cac3a6bd7006ed8ca51b9c4a28
Signed-off-by: Jaechul Lee <jcsing.lee@samsung.com>