tree b27223ea76c43fbfe940644487d22acd2f04ff4c
parent f04e437777cf372d8531ac905729a317ae536e98
author Louis Chang <louischang@google.com> 1591689762 +0800
committer Louis Chang <louischang@google.com> 1591689762 +0800

Prevent NPE while finishing activity

Activity was finished and removed from history before entering
global lock and caused NPE when accessing its task.

Bug: 158299941
Test: existing tests
Change-Id: Iac49bb631653137785edff48c46e2263adbbda64