Backporting the TCP loopback fast path (Windows) improvement to OpenJDK v7

[Martin Sawicki (MS OPEN TECH)]

Hello again,
We'd like to propose to back-port our TCP loopback fast path performance improvement for Windows that was recently accepted into OpenJDK v9 and v8 into v7. 
Just for reference, the original OpenJDK v9 fix just for reference can be found here: http://hg.openjdk.java.net/jdk9/dev/jdk/rev/26e6402772c8. 

Our suggested webrev patch file for OpenJDK *v7* is attached to this message, based on our understanding of the back-porting steps.

Your review and acceptance of this contribution would be appreciated.

Best regards,
Martin Sawicki (and Kirk Shoop, and Valeriy Kopylov)
Microsoft Open Technologies, Inc.
A subsidiary of Microsoft Corp.