[xml] htmlReadDoc and htmlReadIO doesn't build a tree

["Roger Rene Kommer" <kommer artefaktur com>]

Hi,

I have tried to rework my code not using htmlCtxtReadIO, but 
htmlReadDoc, htmlReadIO, htmlReadMemory and/or htmlReadFile.

Strange, but some of these calls doesn't build a tree.
htmlReadFile and htmlReadMemory build a tree, but
htmlReadDoc and htmlReadIO just return an empty document.

I've tried to figure out, what the difference between these calls is.

It seems that in the calls tmlReadDoc and htmlReadIO the sax part
of the context is different, specially ctxt->sax->startElement is 0 in these
calls.

Is this a known bug?
Roger