Iterate over instanced draws in GrGpu rather than above GrBatchTarget

src/gpu/effects/GrDashingEffect.cpp

Index: src/gpu/effects/GrDashingEffect.cpp
diff --git a/src/gpu/effects/GrDashingEffect.cpp b/src/gpu/effects/GrDashingEffect.cpp
index e5fb218d7bc6a93e93bfced5eeb6c65656293e8f..bd2997cdf3707746830a6e8da9789f846829fd0c 100644
--- a/src/gpu/effects/GrDashingEffect.cpp
+++ b/src/gpu/effects/GrDashingEffect.cpp
@@ -599,7 +599,7 @@ public:
             rectIndex++;
         }
         SkASSERT(0 == (curVIdx % 4) && (curVIdx / 4) == totalRectCount);
-        helper.issueDraws(batchTarget);
+        helper.issueDraw(batchTarget);
     }
 
     SkSTArray<1, Geometry, true>* geoData() { return &fGeoData; }