Bug 1469767 - Fix TypeError in addAlertSummaries (#3683)
Bug 1469767 - Fix TypeError in addAlertSummaries (#3683)

Map must return same output type.
edmorley/treeherder,edmorley/treeherder,KWierso/treeherder,KWierso/treeherder,edmorley/treeherder,KWierso/treeherder,edmorley/treeherder,KWierso/treeherder