Merge "Add a NetworkAgent API to indicate that a network will be replaced." am: 9f6e6c4e27 am: 27987f4800

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1987457

Change-Id: Ibc7bbc93db260ce5ab2606c077c8d6f5493b09fb