cc : Move LayerImpl::parent to test properties

cc/layers/layer_impl.cc

Index: cc/layers/layer_impl.cc
diff --git a/cc/layers/layer_impl.cc b/cc/layers/layer_impl.cc
index 14d72ca3b735fbb6e5dd9d1076e47b4b06fecc0e..7dee148ee33ceab519116b6bc70771a060f988af 100644
--- a/cc/layers/layer_impl.cc
+++ b/cc/layers/layer_impl.cc
@@ -44,8 +44,7 @@
 
 namespace cc {
 LayerImpl::LayerImpl(LayerTreeImpl* tree_impl, int id)
-    : parent_(nullptr),
-      mask_layer_id_(-1),
+    : mask_layer_id_(-1),
       mask_layer_(nullptr),
       replica_layer_id_(-1),
       replica_layer_(nullptr),
@@ -112,7 +111,7 @@ LayerImpl::~LayerImpl() {
 }
 
 void LayerImpl::AddChild(std::unique_ptr<LayerImpl> child) {
-  child->SetParent(this);
+  child->test_properties()->parent = this;
   DCHECK_EQ(layer_tree_impl(), child->layer_tree_impl());
   test_properties()->children.push_back(child.get());
   layer_tree_impl_->AddLayer(std::move(child));
@@ -127,10 +126,6 @@ std::unique_ptr<LayerImpl> LayerImpl::RemoveChildForTesting(LayerImpl* child) {
   return layer_tree_impl_->RemoveLayer(child->id());
 }
 
-void LayerImpl::SetParent(LayerImpl* parent) {
-  parent_ = parent;
-}
-
 void LayerImpl::ClearLinksToOtherLayers() {
   mask_layer_ = nullptr;
   replica_layer_ = nullptr;