Use transfer buffer for BatchAtlas texture copies

src/gpu/gl/GrGLBuffer.cpp

Index: src/gpu/gl/GrGLBuffer.cpp
diff --git a/src/gpu/gl/GrGLBuffer.cpp b/src/gpu/gl/GrGLBuffer.cpp
index 24fd59267df44934a4d6afdd209b80c2c393bf26..447bd8b5be664ba5fcdaf46a12bfa8fc9dc4eea0 100644
--- a/src/gpu/gl/GrGLBuffer.cpp
+++ b/src/gpu/gl/GrGLBuffer.cpp
@@ -30,6 +30,12 @@
 
 GrGLBuffer* GrGLBuffer::Create(GrGLGpu* gpu, size_t size, GrBufferType intendedType,
                                GrAccessPattern accessPattern, const void* data) {
+    if (gpu->glCaps().transferBufferType() == GrGLCaps::kNone_TransferBufferType &&
+        (kXferCpuToGpu_GrBufferType == intendedType ||
+         kXferGpuToCpu_GrBufferType == intendedType)) {
+        return nullptr;
+    }
+    
     bool cpuBacked = gpu->glCaps().useNonVBOVertexAndIndexDynamicData() &&
                      GrBufferTypeIsVertexOrIndex(intendedType) &&
                      kDynamic_GrAccessPattern == accessPattern;