Change the message body handling in the HTTP parser

Change the message body handling in the HTTP parser

The message content detection and handling should now be more
correct and according to the specification (RFC 2616 section 4.3).

* Requests with no Content-Length and no Transfer-Encoding have no message body
* Responses with status code 1xx, 204 and 304 have no message body
* Responses which are responses to HEAD requests have no message body

Also added support for detecting chunk-extensions and ignoring these.

R=ajohnsen@google.com

BUG=
TEST=

Committed: https://code.google.com/p/dart/source/detail?r=5722

[Anders Johnsen, 2012-03-21 13:56:28]

LGTM, really cool! :)

https://chromiumcodereview.appspot.com/9812005/diff/1/runtime/bin/http_parser...
File runtime/bin/http_parser.dart (right):

https://chromiumcodereview.appspot.com/9812005/diff/1/runtime/bin/http_parser...
runtime/bin/http_parser.dart:192: if (statusCode < 100 && statusCode > 599) {
Should be ||.

https://chromiumcodereview.appspot.com/9812005/diff/1/runtime/bin/http_parser...
runtime/bin/http_parser.dart:196: // Check whether this response will never have
a body.
I guess that not all values between 100 and 599 are valid - would we gain
anything if we tested against that?

[Søren Gjesse, 2012-03-21 15:37:32]

https://chromiumcodereview.appspot.com/9812005/diff/1/runtime/bin/http_parser...
File runtime/bin/http_parser.dart (right):

https://chromiumcodereview.appspot.com/9812005/diff/1/runtime/bin/http_parser...
runtime/bin/http_parser.dart:192: if (statusCode < 100 && statusCode > 599) {
On 2012/03/21 13:56:28, ajohnsen wrote:
> Should be ||.

Done.

https://chromiumcodereview.appspot.com/9812005/diff/1/runtime/bin/http_parser...
runtime/bin/http_parser.dart:196: // Check whether this response will never have
a body.
On 2012/03/21 13:56:28, ajohnsen wrote:
> I guess that not all values between 100 and 599 are valid - would we gain
> anything if we tested against that?

According to RFC 2616 section 6.1.1 all status codes between 100 and 599 are
valid - though not all defined in the standard. Any status code Sxx (where  1 <=
S && S <= 5) which is not understood should be treated like a S00.