When an ExtractorMediaSource is used in a concatenation, and
probably when using repeat modes, it needs to produce multiple
ExtractorMediaPeriods during usage. Currently we fire a
source info refresh every time a new ExtractorMediaPeriod
instance prepares, which triggers ExoPlayer.EventListener's
onTimelineChanged method. In nearly all cases the timeline is
unchanged after the first ExtractorMediaPeriod is prepared.
This change suppresses these no-op changes.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=162484234
108f4f14f3