[7u6] Request for approval for CR 7152564: Improve CodeSource.matchLocation(CodeSource) performance

[Seán Coffey]

Request to push this to 7u6. Similar fix already in JDK 8 and review 
thread can be found at :

http://mail.openjdk.java.net/pipermail/security-dev/2012-April/004733.html
bug report : http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7152564
Reviewed by : chegar, mullan

regards,
Sean.