Bug 205049 Other plug-ins should be able to define default content generator
Currently only the content generator can define which plug-ins it can be the default for - we need a way for plug-ins to refer back to the marker support for thier own generator.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/MarkerSupportRegistry.java
}
			}
		}
		Iterator keysToRemoveIterator = keysToRemove.iterator();
		while (keysToRemoveIterator.hasNext()) {
			cache.remove(keysToRemoveIterator.next());
		}
	}
	/**
	 * Get the category associated with marker. Return <code>null</code> if
	 * there are none.
	 * 
	 * @param marker
	 * @return String or <code>null</code>
	 */
	public String getCategory(IMarker marker) {
		try {
			return getCategory(marker.getType());
		} catch (CoreException e) {
			Util.log(e);
		}
		return null;
	}
	/**
	 * Get the category associated with markerType. Return <code>null</code>
	 * if there are none.
	 * 
	 * @param markerType
	 * @return String or <code>null</code>
	 */