Bug 61636 added links to the TestFailures page to easily file bugs for failing tests. These bugs always start out with "REGRESSION" in the title and the "Regression" keyword attached. But this isn't really appropriate in the case of a new test that's been failing since it was first added. The failure isn't really a regression in that case.
It would be nice in the TestFailures page could detect this case and give a better bug title and omit the keyword.
Bug 63716 added support for figuring out which files were modified by a particular commit. We could use this to figure out if one of the commits in the regression range added the test.