Use transfer buffer for BatchAtlas texture copies

src/gpu/GrGpu.cpp

Index: src/gpu/GrGpu.cpp
diff --git a/src/gpu/GrGpu.cpp b/src/gpu/GrGpu.cpp
index e14e8929b04bbc84de2fa52f14298befac2733c2..85e6babba39d169fd275718ef4ae2eb5c1075ab1 100644
--- a/src/gpu/GrGpu.cpp
+++ b/src/gpu/GrGpu.cpp
@@ -399,18 +399,24 @@ bool GrGpu::writePixels(GrSurface* surface,
     return this->writePixels(surface, left, top, width, height, config, texels);
 }
 
-bool GrGpu::transferPixels(GrSurface* surface,
+bool GrGpu::transferPixels(GrTexture* texture,
                            int left, int top, int width, int height,
                            GrPixelConfig config, GrBuffer* transferBuffer,
-                           size_t offset, size_t rowBytes) {
+                           size_t offset, size_t rowBytes, GrFence* fence) {
     SkASSERT(transferBuffer);
 
     this->handleDirtyContext();
-    if (this->onTransferPixels(surface, left, top, width, height, config,
+    if (this->onTransferPixels(texture, left, top, width, height, config,
                                transferBuffer, offset, rowBytes)) {
         SkIRect rect = SkIRect::MakeXYWH(left, top, width, height);
-        this->didWriteToSurface(surface, &rect);
+        this->didWriteToSurface(texture, &rect);
         fStats.incTransfersToTexture();
+
+        if (*fence) {
+            this->deleteFence(*fence);
+        }
+        *fence = this->insertFence();
+
         return true;
     }
     return false;