[7u4] Request for Phase 2 approval for CR 7144063: [macosx] Swing JMenu mnemonic doesn't work; hint misleading; cross symbol typed

[Alexander Zuev]

Bug: http://bugs.sun.com/view_bug.do?bug_id=7144063
Webrev: http://cr.openjdk.java.net/~kizune/7144063/webrev.01/
Technical review thread: 
http://mail.openjdk.java.net/pipermail/macosx-port-dev/2012-February/003060.html

Rationale for inclusion in 7u4: menu accelerators work unstable and 
unable to enter some (but not all) special symbols into the text 
component. Low-risk fix reviewed and approved by both QA and R-Team.