Register op version for grid_sampler, test=op_version (PaddlePaddle#2…

…9916)

* register op version for grid_sampler

paddle/fluid/operators/grid_sampler_op.cc

@@ -16,6 +16,7 @@ limitations under the License. */
 #include <memory>
 #include <string>
 #include "paddle/fluid/framework/op_registry.h"
+#include "paddle/fluid/framework/op_version_registry.h"
 #ifdef PADDLE_WITH_CUDA
 #include "paddle/fluid/platform/cudnn_helper.h"
 #endif
@@ -237,3 +238,11 @@ REGISTER_OP_CPU_KERNEL(
     grid_sampler_grad,
     ops::GridSampleGradOpKernel<paddle::platform::CPUDeviceContext, float>,
     ops::GridSampleGradOpKernel<paddle::platform::CPUDeviceContext, double>);
+
+REGISTER_OP_VERSION(grid_sampler)
+    .AddCheckpoint(
+        R"ROC(
+      Upgrade grid_sampler add a new attribute [mode].
+    )ROC",
+        paddle::framework::compatible::OpVersionDesc().NewAttr(
+            "mode", "In order to specify interpolation mode", "bilinear"));