RFR: [8054714] Use StringJoiner where it makes the code cleaner

[Paul Sandoz]

On Aug 9, 2014, at 8:32 AM, Ivan Gerasimov <ivan.gerasimov at oracle.com> wrote:
> Yes, this will surely work faster. I've incorporated your suggestion:
> http://cr.openjdk.java.net/~igerasim/8054714/1/webrev/
> 

Looks ok.

V. minor point, rogue space:

sun/net/www/protocol/http/HttpURLConnection.java	2014-08-09 10:34:38.656983033 +0400

+                if (! cookie.isHttpOnly())

Paul.