Guard GrOp::dumpInfo with SK_DEBUG

This code was only called from debug code, but was still showing up in
Flutter's release build.

Bug: skia:
Change-Id: I0cba323fc3cb14cfe6daf2388cecf5cf317ac9fa
Reviewed-on: https://skia-review.googlesource.com/c/170268
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
diff --git a/src/gpu/ops/GrDrawVerticesOp.cpp b/src/gpu/ops/GrDrawVerticesOp.cpp
index 26372ce..ace2711 100644
--- a/src/gpu/ops/GrDrawVerticesOp.cpp
+++ b/src/gpu/ops/GrDrawVerticesOp.cpp
@@ -114,6 +114,7 @@
     }
 }
 
+#ifdef SK_DEBUG
 SkString GrDrawVerticesOp::dumpInfo() const {
     SkString string;
     string.appendf("PrimType: %d, MeshCount %d, VCount: %d, ICount: %d\n", (int)fPrimitiveType,
@@ -122,6 +123,7 @@
     string += INHERITED::dumpInfo();
     return string;
 }
+#endif
 
 GrDrawOp::FixedFunctionFlags GrDrawVerticesOp::fixedFunctionFlags() const {
     return fHelper.fixedFunctionFlags();