Bug 208101 [Markers] Tasks content has mark completed enabled for non editable tasks
I20071030-0100 Mark completed is enabled for tasks that are not editable
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/provisional/views/markers/ExtendedMarkersView.java
if (service != null)
			builder.setProgressService((IWorkbenchSiteProgressService) service);
		setPartName(generator.getName());
		this.memento = memento;
	}
	/**
	 * Return whether or not group is enabled.
	 * 
	 * @param group
	 * @return boolean
	 */
	boolean isEnabled(MarkerFieldFilterGroup group) {
		return builder.getGenerator().getEnabledFilters().contains(group);
	}
	/**
	 * Return whether or not generator is the selected one.
	 * 
	 * @param generator
	 * @return boolean
	 */
	boolean isShowing(MarkerContentGenerator generator) {
		return this.builder.getGenerator().equals(generator);
	}
	/**
	 * Open the filters dialog for the receiver.
	 */
	void openFiltersDialog() {
		FiltersConfigurationDialog dialog = new FiltersConfigurationDialog(
				new SameShellProvider(getSite().getWorkbenchWindow().getShell()),
				builder.getGenerator());