olly d334dfdcba Fix merging of selected streams.
Playback would fail if a renderer is toggled from consuming from
one child to another in a single step.

Issue: #1900

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=135270356
2016-10-05 21:21:47 +01:00
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2016-10-05 21:21:47 +01:00