Only deref android sms pairing state tracker if it's non-NULL

Bug: 1018860

Change-Id: I75f867e6be9b303c7fcafcc5304788d754bb763b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1882314
Commit-Queue: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#709991}

chromeos/services/multidevice_setup/feature_state_manager_impl.cc

@@ -390,7 +390,8 @@ bool FeatureStateManagerImpl::RequiresFurtherSetup(mojom::Feature feature) {
     return false;
   }
 
-  return !android_sms_pairing_state_tracker_->IsAndroidSmsPairingComplete();
+  return android_sms_pairing_state_tracker_ &&
+         !android_sms_pairing_state_tracker_->IsAndroidSmsPairingComplete();
 }
 
 mojom::FeatureState FeatureStateManagerImpl::GetEnabledOrDisabledState(