[3/4] msxml: Implement removeAttribute

[Alistair Leslie-Hughes]

Mikołaj Zalewski wrote:
>   A problem with this patch is that the user may have an IXMLDOMNode * 
> reference to the attribute node being removed. The xmlFreeProp will free 
> the xmlnode so accessing the IXMLDOMNode could result in memory 
> corruption. Under MSXML it's possible to access such node and even 
> reconnect it e.g. to a different documents (at least I seem to remember 
> such a thing for element nodes).
>   I don't think supporting it is possible with our current reference 
> counting only for the whole document. I was thinking about also keeping 
> reference counts for each connected component and each node. The 
> connected component count could be used to determine if the node can be 
> freed in such a situation and the node count could be used to update the 
> connected component counts if the tree gets split. But so far I haven't 
> written any code (Another possibility is to keep in each node the 
> refcount of the whole subtree starting in this node. This is more 
> elegant but it would take a linear time with respect to the tree height 
> to update the refcount).
> 
> Mikołaj Zalewski
> 
> 
Thanks for pointing this out.  Ill write some tests, and retry again 
shortly.

Alistair Leslie-Hughes