- add a "request" parameter to nsIContentSniffer - make the unknowndecoder implement nsIContentSniffer - make nsBaseChannel do type detection via nsIContentSniffer rather than a stream converter
- add a "request" parameter to nsIContentSniffer - make the unknowndecoder implement nsIContentSniffer - make nsBaseChannel do type detection via nsIContentSniffer rather than a stream converter