message: Fix reference count leak with scatter_nd
  Fixes
diff: @@ -273,6 +273,7 @@ class ScatterNdUpdateOp : public OpKernel {
  if (dtype_ == DT_RESOURCE) {
  Var* v;
  OP_REQUIRES_OK(c, LookupResource(c, HandleFromInput(c, 0), &v));
  + core::ScopedUnref scoped_unref(v);
  Tensor* t = v->tensor();
  params = *t;
  params_shape = params.shape();
  