SDK / exoplayer

This will cause the test to exercise the code path of
instantiating a DummySurface, rendering to it for 10
seconds, then re-targeting the real surface again. For
secure content tests the code path is only exercised if
DummySurface.SECURE_SUPPORTED is true. The logic for
checking this is within MediaCodecVideoRenderer itself,
rather than being part of the test.

Issue: #677

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=157833026