getLocationOnScreen is returning results different from that of 1.3.1 when
the system bar is at the top of the screen. Attached is a sample program
reproducing this.

Steps to reproduce:
1. Place system bar at bottom of screen.
2. Press "setLocation(0, 0)" button.
3. Press "print location on screen" button. (Prints 0, 0)
4. Move system bar to top of screen. (Java app gets pushed down below bar).
5. Redo Step 3. (Prints 0, 0) <-- error
6. Redo Step 2.
7. Redo Step 3. (Prints 0, -<number>)

This does not happen under 1.3.1. This is causing client decorated frames to
jump when being dragged and may possibly be causing the problems for menus
popping up at incorrect offsets.