[automerged blank] DO NOT MERGE: Add a stub class for IpSecService. 2p: 840940321a

Blank merge reason: commit message contains skip directive

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/16826533

Change-Id: I923168d4e63533a9776a299aba13f5b597106138