###@###.### pointed out that we set the background color of the EmbeddedFrame containing the applet, but not the foreground color. This can result in surprising behavior where we paint white on white for some test cases. We should probably set the foreground color as well. Currently we obtain the background color from the GrayBoxPainter, but there is no way to query the foreground color, so that would need to be added as well.
Added method to query the gray box painter's foreground color and code
to set it on the EmbeddedFrame.
Unfortunately I wasn't able to dig up a test case for this and don't
know the exact scenario in which it would take effect. Tested manually
with some simple applets.