[poincare] TreeNode have a zero refcount by default

poincare/include/poincare/tree_node.h

@@ -36,13 +36,6 @@ public:
     m_referenceCounter = refCount;
   }
 
-  void deepResetReferenceCounter() { //TODO make this method private with friends that can access it
-    setReferenceCounter(0);
-    for (TreeNode * t : depthFirstChildren()) {
-      t->setReferenceCounter(1);
-    }
-  }
-
   // Ghost
   virtual bool isGhost() const { return false; }
 

poincare/include/poincare/tree_pool.h

@@ -81,6 +81,7 @@ void TreeByReference::buildGhostChildren() {
     renameNode(copy, false);
     for (TreeNode * child : copy->depthFirstChildren()) {
       renameNode(child, false);
+      child->retain();
     }
     return copy;
   }

poincare/src/tree_by_reference.cpp

@@ -24,7 +24,6 @@ TreeByReference TreeByReference::clone() const {
     return TreeByReference(TreePool::sharedPool()->node(allocationFailureNodeId));
   }
   TreeNode * nodeCopy = TreePool::sharedPool()->deepCopy(myNode);
-  nodeCopy->deepResetReferenceCounter();
   return TreeByReference(nodeCopy);
 }
 
@@ -97,6 +96,7 @@ void TreeByReference::replaceWithAllocationFailureInPlace(int currentNumberOfChi
   //TODO static assert that the size is smaller
   TreeNode * newAllocationFailureNode = TreePool::sharedPool()->deepCopy(staticAllocFailNode);
   newAllocationFailureNode->rename(m_identifier, true);
+  newAllocationFailureNode->retain();
   if (p.isDefined()) {
     assert(indexInParentNode >= 0);
     /* Set the refCount to previousRefCount-1 because the previous parent is

poincare/src/tree_node.cpp

@@ -30,7 +30,7 @@ void TreeNode::rename(int identifier, bool unregisterPreviousIdentifier) {
     TreePool::sharedPool()->unregisterNode(this);
   }
   m_identifier = identifier;
-  m_referenceCounter = 1;
+  m_referenceCounter = 0;
   TreePool::sharedPool()->registerNode(this);
 }
 
@@ -187,7 +187,7 @@ bool TreeNode::hasSibling(const TreeNode * e) const {
 
 TreeNode::TreeNode() :
   m_identifier(TreePool::NoNodeIdentifier),
-  m_referenceCounter(1)
+  m_referenceCounter(0)
 {
 }