Fix handling of MPDs containing SegmentList with SegmentTimeline

[tea]

The current code assumes that SegmentTimeline implies SegmentTemplate. SegmentList+SegmentTimeline combination, while rarely used, is still a valid MPD and should be supported. Thankfully, the fix is trivial.

[dsilhavy]

@tea Thanks for your PR. Following our contribution guidelines, and since this seems to be your first PR, could you please send me a signed copy of dash.js feedback agreement?

[biubiue]

Hi,I use SegmentList and SegmentURL ,when jumping to the specified position in the video, the player crashed. Mpd file like this:
<?xml version="1.0" encoding="utf-8"?> <MPD xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xlink="http://www.w3.org/1999/xlink" xsi:schemaLocation="urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd" profiles="urn:mpeg:dash:profile:isoff-live:2011" type="static" mediaPresentationDuration="PT3M10.4S" maxSegmentDuration="PT5.0S" minBufferTime="PT10.2S"> <ProgramInformation> </ProgramInformation> <ServiceDescription id="0"> </ServiceDescription> <Period id="0" start="PT0.0S"> <AdaptationSet id="0" contentType="video" startWithSAP="1" segmentAlignment="true" bitstreamSwitching="true" frameRate="25/1" maxWidth="1000" maxHeight="1224" par="125:153"> <Representation id="0" mimeType="video/webm" codecs="vp09.00.40.08" bandwidth="1737009" width="1000" height="1224" sar="1:1"> <BaseURL>out-stream0.webm</BaseURL> <SegmentList timescale="1000000" duration="5000000" startNumber="1"> <Initialization range="0-371" /> <SegmentURL mediaRange="372-1207325" /> <SegmentURL mediaRange="1207326-2368408" /> <SegmentURL mediaRange="2368409-3423722" /> <SegmentURL mediaRange="3423723-4506994" /> <SegmentURL mediaRange="4506995-5610467" /> <SegmentURL mediaRange="5610468-6669610" /> <SegmentURL mediaRange="6669611-7745058" /> <SegmentURL mediaRange="7745059-8795162" /> <SegmentURL mediaRange="8795163-9946466" /> <SegmentURL mediaRange="9946467-11139065" /> <SegmentURL mediaRange="11139066-12299272" /> <SegmentURL mediaRange="12299273-13358151" /> <SegmentURL mediaRange="13358152-14669311" /> <SegmentURL mediaRange="14669312-15829422" /> <SegmentURL mediaRange="15829423-16883393" /> <SegmentURL mediaRange="16883394-17974933" /> <SegmentURL mediaRange="17974934-19077695" /> <SegmentURL mediaRange="19077696-20139781" /> <SegmentURL mediaRange="20139782-20691257" /> </SegmentList> </Representation> </AdaptationSet> <AdaptationSet id="1" contentType="audio" startWithSAP="1" segmentAlignment="true" bitstreamSwitching="true"> <Representation id="1" mimeType="audio/webm" codecs="opus" bandwidth="71851" audioSamplingRate="48000"> <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="1" /> <BaseURL>out-stream1.webm</BaseURL> <SegmentList timescale="1000000" duration="5000000" startNumber="1"> <Initialization range="0-398" /> <SegmentURL mediaRange="399-45364" /> <SegmentURL mediaRange="45365-91768" /> <SegmentURL mediaRange="91769-137239" /> <SegmentURL mediaRange="137240-181571" /> <SegmentURL mediaRange="181572-226372" /> <SegmentURL mediaRange="226373-270950" /> <SegmentURL mediaRange="270951-315230" /> <SegmentURL mediaRange="315231-361565" /> <SegmentURL mediaRange="361566-407707" /> <SegmentURL mediaRange="407708-454346" /> <SegmentURL mediaRange="454347-500194" /> <SegmentURL mediaRange="500195-544787" /> <SegmentURL mediaRange="544788-591272" /> <SegmentURL mediaRange="591273-637207" /> <SegmentURL mediaRange="637208-683508" /> <SegmentURL mediaRange="683509-728011" /> <SegmentURL mediaRange="728012-772088" /> <SegmentURL mediaRange="772089-816481" /> <SegmentURL mediaRange="816482-855723" /> <SegmentURL mediaRange="855724-855896" /> </SegmentList> </Representation> </AdaptationSet> </Period> </MPD>