Bug 91899 [Markers] IMarker.setAttribute fails when attributeName = IMarker.LOCATION
Calling setAttribute(IMarker.LOCATION, "foo") on an IMarker instance does nothing---the "Location" column in the Problem View remains blank.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/FieldMessage.java
}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.views.markers.internal.IField#getImage(java.lang.Object)
	 */
	public Image getImage(Object obj) {
		  if (obj == null || !(obj instanceof ProblemMarker)) {
	            return null;
	        }
	       return Util.getImage(((ProblemMarker) obj).getSeverity());
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.views.markers.internal.IField#compare(java.lang.Object,
	 *      java.lang.Object)
	 */
	public int compare(Object obj1, Object obj2) {
		if (obj1 == null || obj2 == null || !(obj1 instanceof ConcreteMarker)
				|| !(obj2 instanceof ConcreteMarker)) {
			return 0;
		}
		ConcreteMarker marker1 = (ConcreteMarker) obj1;
		ConcreteMarker marker2 = (ConcreteMarker) obj2;
		return marker1.getDescriptionKey().compareTo(
				marker2.getDescriptionKey());
	}
}