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
MarkerFilter[] newMarkers = new MarkerFilter[initialFilters.length];
		for (int i = 0; i < initialFilters.length; i++) {
			MarkerFilter newFilter;
			try {
				newFilter = initialFilters[i].makeClone();
			} catch (CloneNotSupportedException exception) {
				ErrorDialog.openError(getShell(),
						MarkerMessages.MarkerFilterDialog_errorTitle,
						MarkerMessages.MarkerFilterDialog_failedFilterMessage,
						Util.errorStatus(exception));
				return;
			}
			newMarkers[i] = newFilter;
		}
		filters = newMarkers;
	}
	/*
	 * (non-Javadoc) Method declared on Dialog.
	 */
	protected void buttonPressed(int buttonId) {
		
		switch (buttonId) {
		case RESET_ID:
			resetPressed();
			markDirty();
			break;
		case SELECT_WORKING_SET_ID:
			workingSetGroup.selectPressed();
			break;
		case SELECT_ALL_ID: