reassign error returned from validateStoragePools so InvalidArgument error code is recorded instead of internal error code

Author: amacaskill

pkg/gce-pd-csi-driver/controller.go

@@ -326,7 +326,9 @@ func (gceCS *GCEControllerServer) CreateVolume(ctx context.Context, req *csi.Cre
 
 	err = validateStoragePools(req, params, gceCS.CloudProvider.GetDefaultProject())
 	if err != nil {
-		return nil, status.Errorf(codes.InvalidArgument, "CreateVolume failed to validate storage pools: %v", err)
+		// Reassign error so that all errors are reported as InvalidArgument to RecordOperationErrorMetrics.
+		err = status.Errorf(codes.InvalidArgument, "CreateVolume failed to validate storage pools: %v", err)
+		return nil, err
 	}
 
 	// Verify that the regional availability class is only used on regional disks.
@@ -351,6 +353,7 @@ func (gceCS *GCEControllerServer) CreateVolume(ctx context.Context, req *csi.Cre
 		if err != nil {
 			return nil, status.Errorf(codes.InvalidArgument, "CreateVolume failed to pick zones for disk: %v", err.Error())
 		}
+		//
 		if len(zones) != 1 {
 			return nil, status.Errorf(codes.Internal, "Failed to pick exactly 1 zone for zonal disk, got %v instead", len(zones))
 		}