http: name anonymous functions in _http_client

[maasencioh]

Checklist

• commit message follows commit guidelines

Description of change

Ref: #8913

[targos]

Please make sure the lines don't exceed 80 characters. make jslint should help you spot the long lines.

[maasencioh]

this is a silly question, but I want to keep the style, should I do

IncomingMessage.prototype._addHeaderLines =
    function _addHeaderLines(headers, n) {...};

or

function _addHeaderLines(headers, n) {...}
IncomingMessage.prototype._addHeaderLines = _addHeaderLines;