Faster edge re-sort, drop trailing edges

(patchset #4 id:60001 of https://codereview.chromium.org/891613003/)"

This reverts commit c319d075eab86cacfd7aba27859b72bbf8fc0a64.

BUG=skia:
TBR=

Review URL: https://codereview.chromium.org/907623002
5 files changed