cc : Move LayerImpl::parent to test properties

cc/trees/occlusion_tracker_unittest.cc

Index: cc/trees/occlusion_tracker_unittest.cc
diff --git a/cc/trees/occlusion_tracker_unittest.cc b/cc/trees/occlusion_tracker_unittest.cc
index 7c113004b237cec3f4686bc88f938e16c8e76c08..e371e54c0e344194531bd4218e385bde8baf940c 100644
--- a/cc/trees/occlusion_tracker_unittest.cc
+++ b/cc/trees/occlusion_tracker_unittest.cc
@@ -300,7 +300,7 @@ class OcclusionTrackerTest : public testing::Test {
 
   void SetReplica(LayerImpl* owning_layer, std::unique_ptr<LayerImpl> layer) {
     // We need to set parent on replica layer for property tree building.
-    layer->SetParent(owning_layer);
+    layer->test_properties()->parent = owning_layer;
     owning_layer->test_properties()->SetReplicaLayer(std::move(layer));
   }