Revert "Revert "add tiler for SkDraw""

This reverts commit 461ef7af88cc966007c464130a971ec86c803f1d.

Prev CL to SkScan_Hairline.cpp fixed the bug that caused the earlier revert.

Bug: skia:
Change-Id: Ifd9a364c7546175be292f726e19465b72196b45e
Reviewed-on: https://skia-review.googlesource.com/112723
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
9 files changed