Iterate over instanced draws in GrGpu rather than above GrBatchTarget

src/gpu/GrTest.cpp

Index: src/gpu/GrTest.cpp
diff --git a/src/gpu/GrTest.cpp b/src/gpu/GrTest.cpp
index 727fbbc662d8f226ab53c08aa5a285b5a63045cf..1017273031320df20e6b25b9955b016355ead911 100644
--- a/src/gpu/GrTest.cpp
+++ b/src/gpu/GrTest.cpp
@@ -199,7 +199,7 @@ private:
 
     void onClearStencilClip(GrRenderTarget*, const SkIRect& rect, bool insideClip) override {}
 
-    void onDraw(const DrawArgs&, const GrVertices&) override {}
+    void onDraw(const DrawArgs&, const GrNonInstancedVertices&) override {}
 
     void onStencilPath(const GrPath* path, const StencilPathState& state) override {}