netty/netty — pull request #3291 by beckje01 (2014-12-24 20:55:02+00:00)
Title: HttpObjectAggregator only set Content-Length is not already set.

Motivation:
HEAD requests will have a Content-Length set that doesn't match the
actual length. So we only want to set Content-Length header if it isn't
already set.

Modifications:
If check around setting the Content-Length

Result:
A HEAD request will no correctly return the specified Content-Length
instead of the body length