The bug here was that we'd create a VideoFrameReleaseTimeHelper
using whatever context DefaultRenderersFactory has, and it would
then hold a reference to that context via DisplayManager. A leak
could then occur if the player outlived the life of the context
used to create it (which would be strange/unusual, but not
impossible).
Issue: #4249
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=198747599
