Bug 1563371 - Find non-gecko decision tasks when needed
Bug 1563371 - Find non-gecko decision tasks when needed

This paves the way to having retriggers work for NSS-Try and
a few other repos.  That repo still needs to generate the right
artifacts.  But this is the Treeherder side of that work.

KWierso/treeherder,KWierso/treeherder,KWierso/treeherder,KWierso/treeherder