Bug 167170 [Markers] Need to check for duplicate filter names
M3 It is currently possible to enter duplicate filter names
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/DialogMarkerFilter.java
String name;
		Collection types = new ArrayList();
		/**
		 * Create a new instance of the receiver with name categoryName.
		 * 
		 * @param categoryName
		 */
		public MarkerCategory(String categoryName) {
			name = categoryName;