fix EditBox bug

fix EditBox bug. When the the EditBox's parent node is added to a node, then set the position of the parent node, the position textField_'s is wrong.
CCEditBoX* pEdit = ...;
CCNode* pNode1 = ...;
CCNode* pNode2 = ...;

pNode1->AddChild(pEdit); // textField_'s is right
pNode2->AddChild(pNode1);// textField_'s is wrong(call by OnEnter)