No auto-pip animation if SysUI is not available

The Launcher crash in the bug is a consequence of SysUI being stopped
due to ANR. In this rare case, we should not start the auto-pip
animation to further crash the launcher.

Bug: 245947669
Test: N/A
Change-Id: I2e99a82d4dccf302788fdb0752f70091fe5a18a3