requestTetheredInterface can be used to put an interface in server mode, which will persist until release() is called on the returned request, or until the requesting process dies. Test: Enabled ethernet tethering with change on top Bug: 130840861 Merged-In: Id96d581acb3fa4e52ca62dd94ec257f56bd3a1ce Change-Id: Id96d581acb3fa4e52ca62dd94ec257f56bd3a1ce (clean cherry-pick from internal branch)