Adds explicit min/max index value fields to GrMesh. This eliminates the
previous assumption that the index values were within the range
[0..vertexCount-1]. In the pattern case we still maintain this
assumption.
Updates GrMesh to hide its fields and handle its new complexity using a
"helper" interface instead.
Adds a unit test for GrMesh.
Bug: skia:
Change-Id: Ia23de72d510f8827cee56072b727fb70a6e46b8d
Reviewed-on: https://skia-review.googlesource.com/17964
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
114a3c0b2b