Don't throw if hint session death link doesn't exist

Bug: 313458589
Bug: 312773552

Test: atest HintManagerServiceTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:ee142e2dbef2e8d05f415a36813e03fbfe1ec6e7)
Merged-In: I985a1869bd7575cad44a21394dc4d68d2248be6c
Change-Id: I985a1869bd7575cad44a21394dc4d68d2248be6c
1 file changed