Keep class implementations of LifecycleObserver, not subinterfaces
Keep class implementations of LifecycleObserver, not subinterfaces

Prior to this change, the 5 or 6 subinterfaces of this type which are present in the library would be kept which also implicit kept LifecycleObserver. This prevented ProGuard/R8 from removing lifecycle in its entirety when unused (as it's not a transitive dependency of support-compat/core).

Bug: 71389427
Test: none
Change-Id: Ifc665d9503cee2fadf5bc683346efce17a29a69c

androidx/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx