Bug 1428045 - Mark string as raw
Bug 1428045 - Mark string as raw

This stops occurrences of `\u` (such as in Windows paths) being
interpreted as malformed Unicode points.

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