Write GPU buffers directly from GrStrokeGeometry

Removes the intermediate stroke representation that GrStrokeGeometry
used to generate. Uses GrOpFlushState::makeVertexStateAtLeast instead
and writes patches directly to a vertex buffer as we iterate the path.
If the vertex buffer runs out of room we simply allocate a new one and
draw the stroke in chunks.

Bug: skia:10419
Bug: skia:10460
Change-Id: Ic743158366e43d4d3f5a4ff97b039d48c9c9c65b
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/305380
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
6 files changed