The nsIDocShellTreeNode supplies the methods for interacting with children
 of a docshell.  These are essentially the methods that turn a single docshell
 into a docshell tree. 
[scriptable, uuid(37f1ab73-f224-44b1-82f0-d2834ab1cec0)]
interface nsIDocShellTreeNode : nsISupports


readonly attribute long childCount


void addChild(in nsIDocShellTreeItem child)

nsIDocShellTreeItem findChildWithName(in wstring aName, in boolean aRecurse, in boolean aSameType, in nsIDocShellTreeItem aRequestor, in nsIDocShellTreeItem aOriginalRequestor)
 Return the child at the index requested.  This is 0-based.

 @throws NS_ERROR_UNEXPECTED if the index is out of range
nsIDocShellTreeItem getChildAt(in long index)

void removeChild(in nsIDocShellTreeItem child)