Optimize GrStrokeFixedCountTessellator

Don't run the cull test until after we've chopped for the first time.
Inline quadTo/conicTo/cubicTo and lift the recursion into separate
methods.

tessellate_GrStrokeFixedCountTessellator bench: 2.37 -> 1.63ms

Bug: skia:10419
Change-Id: Ie7ac32985a8c3e75d554e193543e756dd73e112f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/411196
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
1 file changed