Bug 41773

This is a continuation of bug #31201. The fileEncoding parameter on the
DefaultServlet doesn't go far enough. 
The case I have is this:
I have a webapp that serves some static html files directly to end user. They
are encoded in shift_jis. With the current implementation the response header
says the charset is iso-8859-1 for my jvm. So now I can see the correct
characters in the result page but only if I explicitly tell the browser to show
the page in shift_jis.

I believe the DefaultServlet also needs to pass along the fileEncoding parameter
as the charset in the response content type.

I added the following line to the Default Servlet and it now returns a sensible
content type header for any static html  or text files in my web application.

Compare:
(<)\apache-tomcat-5.5.20-src\container\catalina\src\share\org\apache\catalina\servlets\DefaultServlet.java


738d738
<             if(contentType.toLowerCase().indexOf("charset") == -1 &&
fileEncoding != null) contentType += ";charset="+fileEncoding; 

It would be great if this could be applied to the official tomcat distribution.
Thanks