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
1 file changed