Benchmark: add asserts for common failures in native tests

This patch also updates 'cout' to ALOG for Atest and changes
related to formatting

Test: extractorTest -P /data/local/tmp/res/
Test: muxerTest -P /data/local/tmp/res/
Test: decoderTest -P /data/local/tmp/res/
Test: encoderTest -P /data/local/tmp/res/
Test: C2DecoderTest -P /data/local/tmp/res/
Test: C2EncoderTest -P /data/local/tmp/res/

Bug: 146623471

Change-Id: I9adc20ef994cba81482185f64fcbd6a266f0d417