Revert of Preliminary attempt to remove batch tracker

src/gpu/GrBatchTarget.h

Index: src/gpu/GrBatchTarget.h
diff --git a/src/gpu/GrBatchTarget.h b/src/gpu/GrBatchTarget.h
index 61f12d81698224443d55237f6a561503753897ba..f317f3046e9c60786872d369863c4b4227439e5a 100644
--- a/src/gpu/GrBatchTarget.h
+++ b/src/gpu/GrBatchTarget.h
@@ -104,6 +104,12 @@
         fInlineUploads.reset();
     }
 
+    // TODO This goes away when everything uses batch
+    GrBatchTracker* currentBatchTracker() {
+        SkASSERT(!fFlushBuffer.empty());
+        return &fFlushBuffer.back().fBatchTracker;
+    }
+
     const GrDrawTargetCaps& caps() const { return *fGpu->caps(); }
 
     GrResourceProvider* resourceProvider() const { return fGpu->getContext()->resourceProvider(); }