Merge "Support testing upload/download packets" am: 139f43509e am: 911bd90d33 am: 8d8cf85d5c am: 231485f7f0

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1903463

Change-Id: I6e689c549628aca9ac7ee390aa8118129e6a48f3