Remove redundant notice property. am: 46d7b5a059 am: 52dcf3c62a am: 9691878c3f am: d7d6650065 am: 3d56a20125

Original change: https://android-review.googlesource.com/c/platform/external/exoplayer/+/2154455

Change-Id: I78c18f094faafe137fb72e29bb5f5353f3a2b0fb
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>