fixes bug 308858 "Use NS_ERROR_INVALID_CONTENT_ENCODING when encodings don't match" patch by Vidar Braut Haarr <vhaarr+bmo@gmail.com>, r+sr=darin

netwerk/protocol/http/src/nsHttpChannel.cpp

@@ -1131,7 +1131,7 @@ nsHttpChannel::ProcessPartialContent()
     if (PL_strcasecmp(mResponseHead->PeekHeader(nsHttp::Content_Encoding),
                       mCachedResponseHead->PeekHeader(nsHttp::Content_Encoding))
                       != 0) {
-        Cancel(NS_ERROR_UNEXPECTED); // XXX need better error code
+        Cancel(NS_ERROR_INVALID_CONTENT_ENCODING);
         return CallOnStartRequest();
     }