Refactors common scope id setup code into utility function Bug: 279691947 Test: atest NetworkStackIntegrationTests NetworkStackRootTests Test: atest CtsNetTestCases:android.net.cts.NsdManagerTest (cherry picked from https://android-review.googlesource.com/q/commit:2261f78e3bab363260be4065c893e36b375df497) Merged-In: Id15b745329f641cc9a1bd45eb5478ecdebd66d0d Change-Id: Id15b745329f641cc9a1bd45eb5478ecdebd66d0d