Merge "media: clarify MediaFormat.KEY_FRAME_RATE for video encoders" into tm-dev am: 42e8a228

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18605610



Change-Id: Ief786006566a9953c6be2850a595450fa1a12661
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>