gst/matroska/: Handle return values from pull_range in a more granular way to properl...

gst/matroska/: Handle return values from pull_range in a more granular way to properly shut down on seeks.

Original commit message from CVS:
* gst/matroska/ebml-read.c: (gst_ebml_read_peek_bytes),
(gst_ebml_read_pull_bytes), (gst_ebml_read_element_id),
(gst_ebml_read_element_length), (gst_ebml_peek_id),
(gst_ebml_read_skip), (gst_ebml_read_buffer),
(gst_ebml_read_bytes), (gst_ebml_read_uint), (gst_ebml_read_sint),
(gst_ebml_read_float), (gst_ebml_read_ascii), (gst_ebml_read_utf8),
(gst_ebml_read_date), (gst_ebml_read_master),
(gst_ebml_read_binary), (gst_ebml_read_header):
* gst/matroska/ebml-read.h:
* gst/matroska/matroska-demux.c:
(gst_matroska_demux_combine_flows), (gst_matroska_demux_reset),
(gst_matroska_demux_read_track_encodings),
(gst_matroska_demux_add_stream),
(gst_matroska_demux_handle_src_query),
(gst_matroska_demux_handle_seek_event),
(gst_matroska_demux_init_stream),
(gst_matroska_demux_parse_tracks),
(gst_matroska_demux_parse_index_cuetrack),
(gst_matroska_demux_parse_index_pointentry),
(gst_matroska_demux_parse_index), (gst_matroska_demux_parse_info),
(gst_matroska_demux_parse_metadata_id_simple_tag),
(gst_matroska_demux_parse_metadata_id_tag),
(gst_matroska_demux_parse_metadata),
(gst_matroska_demux_sync_streams),
(gst_matroska_demux_push_hdr_buf),
(gst_matroska_demux_push_flac_codec_priv_data),
(gst_matroska_demux_push_xiph_codec_priv_data),
(gst_matroska_demux_add_wvpk_header),
(gst_matroska_demux_check_subtitle_buffer),
(gst_matroska_demux_parse_blockgroup_or_simpleblock),
(gst_matroska_demux_parse_cluster),
(gst_matroska_demux_parse_contents_seekentry),
(gst_matroska_demux_parse_contents),
(gst_matroska_demux_loop_stream_parse_id),
(gst_matroska_demux_loop_stream), (gst_matroska_demux_loop):
* gst/matroska/matroska-demux.h:
* gst/matroska/matroska-ids.h:
Handle return values from pull_range in a more granular way to properly
shut down on seeks.
Combine return values from push.
Implement proper error handling.
Prepare for handling seeking correctly.