Method fixScrollbar

ij/src/main/java/ij/gui/GUI.java:616–619

Works around an OpenJDK bug on Windows that causes the scrollbar thumb color and background color to be almost identical.

(Scrollbar sb)

	 * color to be almost identical.
	*/
	public static final void fixScrollbar(Scrollbar sb) {
		if (IJ.isWindows())
			sb.setBackground(scrollbarBackground);
	}
	
	/** Returns a new NonBlockingGenericDialog with the given title,
	 *  except when Java is running in headless mode, in which case