RFR 8224849 : Flag (?U:...) is allowed for non-capturing groups

[Ivan Gerasimov]

Hello!

When the fix for JDK-7039066 (which added support for the flag 
UNICODE_CHARACTER_CLASS and corresponding embedded expression (?U)) was 
integrated back in JDK 7, the documentation for the non-capturing groups 
was not updated accordingly.

Would you please help review the fix, which only updates the javadoc?

BUGURL: https://bugs.openjdk.java.net/browse/JDK-8224849
WEBREV: http://cr.openjdk.java.net/~igerasim/8224849/00/webrev/

Thanks in advance!

-- 
With kind regards,
Ivan Gerasimov