RFR: 8185898: setRequestProperty(key, null) results in HTTP header without colon in request

[Chris Hegarty]

Julia,

> On 9 Aug 2019, at 13:40, Julia Boes <julia.boes at oracle.com> wrote:
> 
> Hi,
> 
> Please find an alternative fix below. Chris and Daniel suggested to add a new method MessageHeader::isRequestline rather than a separate data field for the requestline. A whitebox test was added with the method testMessageHeader.
> 
> Updated webrev: http://cr.openjdk.java.net/~michaelm/jboes/8185898/webrev.4/

LGTM.

-Chris.