Bug 221521 [Markers] New markers API needs to be pared down
We have too much API in some of the new classes and they can be moved to internals
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/MarkersPropertyPage.java
/* (non-Javadoc)
	 * @see org.eclipse.jface.preference.PreferencePage#performOk()
	 */
	public boolean performOk() {
		if (marker == null || Util.isEditable(marker)) {
			saveChanges();
		}
		return super.performOk();
	}
	/**
	 * Saves the changes made in the dialog if needed. Creates a new marker if
	 * needed. Updates the existing marker only if there have been changes.
	 */
	private void saveChanges() {
		Map attrs;
		try {
			attrs = marker.getAttributes();
		} catch (CoreException e) {
			attrs = new HashMap();
			Policy.handle(e);
		}
		attrs.put(IMarker.MESSAGE, descriptionText.getText());
		
		if (priorityCombo != null) {
			int priority = IMarker.PRIORITY_NORMAL;
			int index = priorityCombo.getSelectionIndex();
			if (index == priorityCombo
					.indexOf(MarkerMessages.propertiesDialog_priorityHigh))
				priority = IMarker.PRIORITY_HIGH;
			else if (index == priorityCombo