This is the same fix backported from the JDK 8 to JDK 7u10 without changes: bug: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7194469 webrev: http://cr.openjdk.java.net/~alexsch/7194469/webrev.01/
The TextField control starts beeping on some keys pressing (enter, up, down...) after switching the EDIT control to RICHEDIT.
The fix disables and enables the beeper by SystemParametersInfo method with the zero value in the fWinIni param for the RICHEDIT control if requested keys are pressed.
Thanks, Alexandr.