RFR: 8153666: Optimize Formatter.formatMessage

[Daniel Fuchs]

Hi,

Please find below a patch for a small optimization
in Formatter.formatMessage.
This patch also removed the synchronized keyword which
was there for historical reasons - but which has
become needless.

More background available at:
https://bugs.openjdk.java.net/browse/JDK-8153666
(thanks Martin!)
and
http://stackoverflow.com/questions/36433146/why-is-the-formatmessage-method-in-java-util-logging-formatter-synchronized
(thanks Jason!)

bug:
8153666: Optimize Formatter.formatMessage
https://bugs.openjdk.java.net/browse/JDK-8153666


patch:
http://cr.openjdk.java.net/~dfuchs/webrev_8153666/webrev.00

best regards, and thanks to all who provided suggestions and
archeological background!

-- daniel