Bugfix for sendBody() and chunked utf8 strings

Http expects chunked byte offsets and ignores the encoding specified in the
header. This patch makes node behave accordingly.

Bug report:
http://groups.google.com/group/nodejs/browse_thread/thread/ab701d49cb059317

lib/http.js

@@ -283,7 +283,7 @@ OutgoingMessage.prototype.sendHeaderLines = function (first_line, headers) {
 
 OutgoingMessage.prototype.sendBody = function (chunk, encoding) {
   if (this.chunked_encoding) {
-    this.send(chunk.length.toString(16));
+    this.send(process._byteLength(chunk, encoding).toString(16));
     this.send(CRLF);
     this.send(chunk, encoding);
     this.send(CRLF);

test/mjsunit/test-http-chunked.js

@@ -0,0 +1,22 @@
+process.mixin(require("./common"));
+var http = require("http");
+var PORT = 8888;
+
+var UTF8_STRING = "Il était tué";
+
+var server = http.createServer(function(req, res) {
+  res.sendHeader(200, {"Content-Type": "text/plain; charset=utf8"});
+  res.sendBody(UTF8_STRING, 'utf8');
+  res.finish();
+});
+server.listen(PORT);
+
+http.cat("http://localhost:"+PORT+"/", "utf8")
+  .addCallback(function (data) {
+    assertEquals(UTF8_STRING, data);
+    server.close();
+  })
+  .addErrback(function() {
+    assertUnreachable('http.cat should succeed in < 1000ms');
+  })
+  .timeout(1000);