Daniel Stone authored May 21, 2020 and Ana Rute Mendes committed Jun 22, 2020

If we have a child task which we can't access, ManiphestTaskQuery will
raise an exception; trying to view the workboard, this will bubble up as
a policy exception which will (incorrectly) tell the viewer they can't
access the project.

Catch any exceptions whilst trying to calculate overall progress, and
ignore those restricted child tasks.