ROIAlignGrad kernel output size is wrong

mindspore/ccsrc/backend/kernel_compiler/gpu/nn/roi_align_grad_gpu_kernel.h

@@ -91,13 +91,14 @@ class ROIAlignGradGpuFwdKernel : public GpuKernel {
     roi_end_mode_ = 1;
 
     // Get channels, height & width
+    batch_size_ = xdiff_shape_[0];
     channels_ = xdiff_shape_[1];
     height_ = xdiff_shape_[2];
     width_ = xdiff_shape_[3];
 
     // Get output_shape
-    output_shape_ = {roi_rows_, channels_, height_, width_};
-    output_size_ = roi_rows_ * channels_ * height_ * width_ * sizeof(T);
+    output_shape_ = {batch_size_, channels_, height_, width_};
+    output_size_ = batch_size_ * channels_ * height_ * width_ * sizeof(T);
 
     InitSizeLists();
     return true;
@@ -120,6 +121,7 @@ class ROIAlignGradGpuFwdKernel : public GpuKernel {
 
   int roi_rows_;
   int roi_cols_;
+  int batch_size_;
   int channels_;
   int height_;
   int width_;