cc: Stop creating unused 0 property tree nodes other than transform

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 900ee29e5747f32de7d18699977f3abfee5440c2..52f79ccba01bee0cccfcddbb3a0dcc3d5d1b97c1 100644
--- a/cc/layers/layer_impl.cc
+++ b/cc/layers/layer_impl.cc
@@ -1241,13 +1241,13 @@ bool LayerImpl::InsideReplica() const {
   EffectTree& effect_tree = layer_tree_impl_->property_trees()->effect_tree;
   EffectNode* node = effect_tree.Node(effect_tree_index_);
 
-  while (node->id > 0) {
-    if (node->data.replica_layer_id != -1)
+  while (node->id > EffectTree::kRootNodeId) {
+    if (node->data.replica_layer_id != EffectTree::kInvalidNodeId)

[ajuma, 2016/06/22 13:29:50]

Layer::INVALID_ID since this is a layer id

       return true;
     node = effect_tree.Node(node->data.target_id);
   }
 
-  return false;
+  return node->data.replica_layer_id != EffectTree::kInvalidNodeId;

[ajuma, 2016/06/22 13:29:50]

Here too, Layer::INVALID_ID

 }
 
 float LayerImpl::GetIdealContentsScale() const {