Also add starting window when activity is not alive

The fact whether the process is running or not is not necessarily
a reason to not show a starting window. Sometimes the process with
an activity gets killed, but later gets restarted because of some
broadcast or service without recreating the activity. In this
case, we still need a splash screen to hide the recreation delay,
which is usually as expensive as if the process is not running.

Test: Open Calendar, kill `pid calendar`, reopen it, make sure
starting window is shown.
Test: As above but with a couple of other apps - with and widhout
trampoline activities.
Test: Boot freshly and open a couple of apps from recents

Change-Id: I8c4f928fca77b5446cab55c89bc69adbaaaa8da3
Fixes: 37951698