Bug 214492 [Markers] Need to be able to add filters to existing markers views
Currently you can only add filters to a new markerContentProvider. We need to able to bind them to existing markerContentProviders as well.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/TypeMarkerGroup.java
field = new FieldCategory();
		markerField = new TypeMarkerField(this);
	}
	
	/* (non-Javadoc)
	 * @see org.eclipse.ui.views.markers.internal.MarkerGroup#getId()
	 */
	public String getId() {
		return Util.TYPE_MARKER_GROUPING_ID;
	}
	
	/* (non-Javadoc)
	 * @see org.eclipse.ui.views.markers.internal.MarkerGroup#getTitle()
	 */
	public String getTitle() {
		return name;
	}
	
	/* (non-Javadoc)
	 * @see org.eclipse.ui.views.markers.internal.MarkerGroup#isGroupingFor(java.lang.String)
	 */
	public boolean isGroupingFor(String id) {
		MarkerContentGenerator generator = MarkerSupportRegistry.getInstance().getGenerator(id);
		if(generator == null)
			return false;
		
		return generator.getMarkerTypes().size() > 1;
	}
}