Benchmark: Add SDK Muxer

Test: adb shell am instrument -w -r -e class \
      'com.android.media.benchmark.tests.MuxerTest' \
      com.android.media.benchmark.test/androidx.test.runner.AndroidJUnitRunner

Bug: 140051680

Change-Id: I39bbc02b66e7e127a61431ea89bf1e5c464063ce
3 files changed