mozilla/servo — pull request #2621 by pcwalton (2014-06-09 04:31:31+00:00)
Title: gfx: Binary search for the start position when iterating over the slices

in a text run.

This makes painting of text display items faster and matches what Gecko
does.

Incorrect automatic derivation of `TotalOrd` broke it last time.

r? @brson