In Java Cache Viewer, if the menu is open, either enter or space should activate the selected action

Tested OS : All
Tested Build : Mustang build 48

Steps to reproduce :
1. Install mustang build 48
2. Clear Cache
3. Import notepad application (./javaws -import http://java.sun.com/products/javawebstart/apps/notepad.jnlp)
4. Launch Java Cache Viewer
5. Select notepad application
6. Press Shift+F10
Menu will be opened
7. Choose Delete menu item using the down arrow key
8. Now press Enter key

Actual Behaviour : The application is launched
Expected Behaviour : The application should be deleted.

If the menu is open, either enter or space bar key should activate the selected action.