Aborting the progress gauge

When something unexpected happens to the progress gauge, it just sticks around in the minibuffer. It seems impossible to remove it. Changing buffers doesn't help. Opening a new frame helps, though. You can repeat it by starting the font-lock of a large buffer, and clicking somewhere in the echo area other than the "Stop" button. This results in "not over a window" error. I think the echo area progress gauge should behave like an echo area message -- removed at the first possible opportunity.