switch unique_ptr with deleter to GrMemoryPool

I switched GrOps from using GrOpMemoryPool to
GrMemoryPool, but I forgot to switch over the
GrOp::Owner. Make sure the GrOp::Owner works for
both new/delete and GrMemoryPool.

In addition, convert one last unique_ptr<GrOp> to
GrOp::Owner.

Change-Id: I660ad77bee0f060f263ff2ed07974afb83063441
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/330097
Commit-Queue: Herb Derby <herb@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
diff --git a/src/gpu/ops/GrSimpleMeshDrawOpHelper.h b/src/gpu/ops/GrSimpleMeshDrawOpHelper.h
index b016050..181249c 100644
--- a/src/gpu/ops/GrSimpleMeshDrawOpHelper.h
+++ b/src/gpu/ops/GrSimpleMeshDrawOpHelper.h
@@ -199,7 +199,7 @@
     GrProcessorSet* processorSet = new (setMem)  GrProcessorSet{std::move(paint)};
     return Owner{new (bytes) Op(processorSet, color, std::forward<Args>(args)...)};
 #else
-    GrOpMemoryPool* pool = context->priv().opMemoryPool();
+    GrMemoryPool* pool = context->priv().opMemoryPool();
     char* bytes = (char*)pool->allocate(sizeof(Op) + sizeof(GrProcessorSet));
     char* setMem = bytes + sizeof(Op);
     GrProcessorSet* processorSet = new (setMem)  GrProcessorSet{std::move(paint)};