olly b37e9f6980 For both alignment cue setting value and position cue setting alignment value, ... allow "center". This value (and not "middle") is listed in https://w3c.github.io/webvtt/ ( WebVTT: The Web Video Text Tracks Format, Draft Community Group Report, 21 December 2015). Leaving the behavior for "middle" unchanged. It was the value listed in older drafts, e.g. https://www.w3.org/TR/2014/WD-webvtt1-20141113/ ( W3C First Public Working Draft 13 November 2014 ) ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=117220612		2016-06-15 19:37:44 +01:00
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exoplayer	For both alignment cue setting value and position cue setting alignment value,	2016-06-15 19:37:44 +01:00