Add a GrSimpleMeshDrawOpHelper CreatePipeline method that doesn't require a GrFlushState

This CL also adds helper functions (i.e., createPipeline and createPipelineWithStencil) to better encapsulate pipeline creation.

This is a first step towards making GrSimpleMeshDrawOpHelper surface its GrProgramInfos.

Bug: skia:9455
Change-Id: Ic6cc7a01383e42436305358a9b193958d862786c
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/273556
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
21 files changed