Bug 213040 [Markers] Selected filters not being kept on restart
When I select "Warnings on Selection" and then restart it is not selected when I come back in. We need to retain these selections. Note this is only a problem when selecting from the menu - from the dialog works fine.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/provisional/views/markers/MarkerContentGenerator.java
IResource next = (IResource) elements[idx]
					.getAdapter(IResource.class);
			if (next != null) {
				result.add(next);
			}
		}
		return (IResource[]) result.toArray(new IResource[result.size()]);
	}
	/**
	 * Get the sort direction of field
	 * 
	 * @param field
	 * @return int one of {@link MarkerComparator#ASCENDING} or
	 *         {@link MarkerComparator#DESCENDING}
	 */
	int getSortDirection(MarkerField field) {
		if (getComparator().descendingFields.contains(field))
			return MarkerComparator.DESCENDING;
		return MarkerComparator.ASCENDING;
	}
	/**
	 * Get the fields that this content generator is displaying.
	 * 
	 * @return {@link MarkerField}[]
	 */
	MarkerField[] getVisibleFields() {
		return visibleFields;
	}
	/**
	 * Initialise the receiver from the configuration element. This is done as a