Original commit message from CVS:
* gst/qtdemux/qtdemux.c: (gst_qtdemux_class_init),
(gst_qtdemux_init), (gst_qtdemux_dispose),
(gst_qtdemux_add_stream), (qtdemux_parse_trak):
Series of memleak fixes:
- Unref the GstAdapter in finalize.
- Use gst_pad_new_from_static_template(), shorter and safer.
- Free unused QtDemuxStream when not used.