Do not throw RuntimeException from stopScan().

This is a clean cherry-pick from
https://android-review.googlesource.com/#/c/platform/frameworks/base/+/635589/

Bug:73750871
Test: Unit Test
Change-Id: I640093627c103fe1d2fe5707e6854ba748789919
Merged-in: I640093627c103fe1d2fe5707e6854ba748789919
(cherry picked from commit 5e366e31)