olly b6b84839ed Add ErrorMessageProvider to util package
It's needed in multiple places. MediaSessionConnector uses it
today. Our leanback connector will also use it. Maybe
SimpleExoPlayerView should use one too, to show the message to
the user when an error occurs.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=164720020
2017-08-10 13:19:12 +01:00
..
2017-08-07 13:38:15 +01:00