Update AllPackageInfosLiveData in onUpdate

Because AllPackageInfosLiveData did not actually update its value in
onUpdate (instead checking for new LiveDatas, from which to update its
value), this meant that if it came active while its source LiveDatas
were already active and non-stale, it would never get an update from
them, and would remain stale

Fixes: 206455664
Test: Manual
Change-Id: I5b4cbe3daa9fadea758c9f033ac085a1dcad4de7