olly ad857852e5 Discard subtitles with invalid positions
textWidth can be negative if textLeft extends parentRight (i.e.
the subtitle is positioned entirely off the screen to the RHS).
We should just discard and log a warning in this case.

Issue: #2497

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148481310
2017-02-28 13:47:18 +00:00
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2017-01-13 17:27:25 +00:00