Remove custom SkSort algorithms.

SortBench shows that SkTQSort and SkTHeapSort are inferior to std::sort.
The difference is small on randomized inputs, but quite significant for
semi-ordered inputs (forward/backward/repeated). There doesn't seem to
to be any compelling advantage to SkTQSort.

Nanobench results: https://screenshot.googleplex.com/9JOLV1d6Z0u

(These performance numbers are from an optimized build my local machine;
it's possible that we might see different results on the test bots.)

Change-Id: Iaf19563041547eae7de2953be249129108f093b1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/302295
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
44 files changed