1984349 - Improve subtests page readability by implementing sorting based on magnitude

Status: NEW

(Testing :: PerfCompare, enhancement)

Description

[Acasandrei Beatrice (needinfo me)]

Enhancement requested in the recent form "Feedback: Compare View vs. PerfCompare" that we sent to users:
I find it easier to scan sub-test results in Compare View. In particular, sorting by Delta in Compare View will order the "magnitude of difference" column so that it's easy to scroll through and see the overall trend of changes. In PerfCompare, there's no "magnitude of difference" column (which makes it harder to tell at a glance which tests got better/worse), and sorting by Delta will put large positive changes and large negative changes at the same end of the list. If I want to get a quick sense of the distribution of changes from a particular patch, Compare View is much more efficient.

Another feedback that is related:
No color cues to draw the eye: In the old perfherder view, a regression/improvement line item has the "magnitude of difference" header, which has the relative magnitude of change, and a color coding (red vs. green). This makes it easy to identify at a glance the rows which are regressions and which are improvements, and their relative magnitude %