tonihei 19aa69e0f4 Remove child data holder helper from AbstractConcatenatedTimeline.
This helper class required a scratch instance to write on. Such a scratch
instance may violate the immuatability of the timelines if used by multiple
threads simultaneously.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=163992458
2017-08-02 20:23:54 +01:00
..
2017-08-02 13:33:46 +01:00