ext/alsa/gstalsa.c: Alsa should trigger an error if it failed opening the audio device.

ext/alsa/gstalsa.c: Alsa should trigger an error if it failed opening the audio device.

Original commit message from CVS:
2004-02-16  Julien MOUTTE <julien@moutte.net>

* ext/alsa/gstalsa.c: (gst_alsa_open_audio),
(gst_alsa_timestamp_to_bytes): Alsa should trigger an error if it
failed opening the audio device.
* sys/ximage/ximagesink.c: (gst_ximagesink_ximage_new),
(gst_ximagesink_ximage_destroy), (gst_ximagesink_ximage_put),
(gst_ximagesink_xwindow_new), (gst_ximagesink_xwindow_destroy),
(gst_ximagesink_xwindow_resize), (gst_ximagesink_xwindow_clear),
(gst_ximagesink_renegotiate_size), (gst_ximagesink_handle_xevents),
(gst_ximagesink_xcontext_get), (gst_ximagesink_xcontext_clear),
(gst_ximagesink_change_state), (gst_ximagesink_chain),
(gst_ximagesink_set_xwindow_id): Clearing window in READY TO PAUSED.
Removing some useless g_return_if_fail like wingo suggested.
* sys/xvimage/xvimagesink.c: (gst_xvimagesink_xvimage_new),
(gst_xvimagesink_xvimage_destroy), (gst_xvimagesink_xvimage_put),
(gst_xvimagesink_xwindow_new), (gst_xvimagesink_xwindow_destroy),
(gst_xvimagesink_xwindow_resize), (gst_xvimagesink_xwindow_clear),
(gst_xvimagesink_update_colorbalance),
(gst_xvimagesink_handle_xevents), (gst_xvimagesink_xcontext_get),
(gst_xvimagesink_xcontext_clear),
(gst_xvimagesink_get_fourcc_from_caps),
(gst_xvimagesink_change_state), (gst_xvimagesink_chain),
(gst_xvimagesink_set_xwindow_id),
(gst_xvimagesink_colorbalance_list_channels),
(gst_xvimagesink_colorbalance_set_value),
(gst_xvimagesink_colorbalance_get_value): Clearing window in READY TO
PAUSED. Removing some useless g_return_if_fail like wingo suggested.