Rename GrPipeline::Flags to GrPipeline::InputFlags

Renames the Flags to InputFlags and makes it a strongly typed enum.
Simplifies the relationship between GrSimpleMeshDrawOpHelper::Flags
and GrPipeline::InputFlags.

Bug: skia:
Change-Id: Ia25b8526ff96a47428dfbb82da18dbebdd382c5b
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/204906
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/ops/GrFillRRectOp.cpp b/src/gpu/ops/GrFillRRectOp.cpp
index 12d4300..a302099 100644
--- a/src/gpu/ops/GrFillRRectOp.cpp
+++ b/src/gpu/ops/GrFillRRectOp.cpp
@@ -741,7 +741,7 @@
 
     GrPipeline::InitArgs initArgs;
     if (GrAAType::kMSAA == fAAType) {
-        initArgs.fFlags = GrPipeline::kHWAntialias_Flag;
+        initArgs.fInputFlags = GrPipeline::InputFlags::kHWAntialias;
     }
     initArgs.fCaps = &flushState->caps();
     initArgs.fResourceProvider = flushState->resourceProvider();