[automerger skipped] [DO NOT MERGE] Fix Settings crash when setting a null...

[automerger skipped] [DO NOT MERGE] Fix Settings crash when setting a null ringtone am: d94b73b3 am: 58880a0b -s ours am: 1e688667 -s ours am: 1da60c2f -s ours am: 4129c273 -s ours am: e6135eeb -s ours am: eb1d86b6 -s ours

am skip reason: subject contains skip directive

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Settings/+/18356598



Change-Id: I65536a8d3002a3945fce0abdea47f3f3a5859be3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>