Add a "bisect" mode to dm for debugging path drawing

Bug: skia:
Change-Id: Idc841545dfe3d33f43c1c8a3cf23199c322f7b11
Reviewed-on: https://skia-review.googlesource.com/156929
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
3 files changed