olly 153c0aef2b Rework MediaPeriod track selection
This change allows MediaPeriod instances to replace
SampleStream instances when the selection isn't changing.
It also allows MediaPeriod instances to retain a
SampleStream but indicate that the renderer consuming
from it needs to be reset.

The change is used to fix the ref'd bug, and is used to
do the same thing in HLS without the need for the source
to report a discontinuity. Note that reporting discontinuity
could cause unnecessary failure when used as a child of
MergingMediaSource.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=129971782
2016-08-31 13:22:15 +01:00
..
2016-08-31 13:22:15 +01:00