Fix nullptr segv am: d66ecf171c am: b953d663ea

Change-Id: I383c1f707e07a4bd4ce095e15510ea73058bd956
diff --git a/dynamic_partition_control_android.cc b/dynamic_partition_control_android.cc
index 072a3ec..938a75b 100644
--- a/dynamic_partition_control_android.cc
+++ b/dynamic_partition_control_android.cc
@@ -621,7 +621,8 @@
 }
 
 bool DynamicPartitionControlAndroid::FinishUpdate() {
-  if (snapshot_->GetUpdateState() == UpdateState::Initiated) {
+  if (GetVirtualAbFeatureFlag().IsEnabled() &&
+      snapshot_->GetUpdateState() == UpdateState::Initiated) {
     LOG(INFO) << "Snapshot writes are done.";
     return snapshot_->FinishedSnapshotWrites();
   }