[automerger skipped] Fix the mStopTimeNs not be reset in Stopwatch#Restart am: 0c423089 am: 7f626e3b am: bab27c2d -s ours

am skip reason: Change-Id Ib83ceb70af3491dacbb4a45f65ef38661ae75e32 with SHA-1 afceb9df is in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/NetworkStack/+/11931260

Change-Id: I029358b5bb4473e8464483d94d39449bba8231ad