Rename android.media.MediaTranscodeManager -> MediaTranscodingManager am: 97423c97f3 am: f16e2e4f29

Original change: https://googleplex-android-review.googlesource.com/c/platform/prebuilts/sdk/+/15521812

Change-Id: I7f372e86b6bd0fa6469218f0ed0e720882797547