adsLoader.contentComplete was called twice which led to postrolls not seeing
the STARTED event.
Also make the onPositionDiscontinuity handler easier to follow by renaming
variables, and remove the adGroupIndex field.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=161537765
Once background and resuming is supported, the ads loader will be kept when the
player is destroyed and recreated. Move the state relating to the structure of
ads and what ads have been loaded/played out of the media source and into the
loader so the information is not lost when the source is released, in
preparation for supporting background and resuming.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=161503571
This also adds support for seeking in periods with midroll ads.
Remove Timeline.Period.isAd.
Issue: #2617
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=160510702
This will allow MediaSources to provide MediaPeriods that correspond to ad
breaks in a timeline period rather than content for a timeline period, in a
future change.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=160267841
continueLoading may be called during preparation, but this is not
handled correctly in the case where a deferred period doesn't
have a source yet.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=158696539