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
composite.setLayout(layout);
		priorityCombo = new Combo(composite, SWT.READ_ONLY);
		priorityCombo.setItems(new String[] {
				MarkerMessages.propertiesDialog_priorityLow,
				MarkerMessages.propertiesDialog_priorityNormal,
				MarkerMessages.propertiesDialog_priorityHigh });
		priorityCombo.select(marker.getAttribute(IMarker.PRIORITY,
				IMarker.PRIORITY_NORMAL));
		priorityCombo.setEnabled(Util.isEditable(marker));
		completedCheckbox = new Button(composite, SWT.CHECK);
		completedCheckbox.setText(MarkerMessages.propertiesDialog_completed);
		GridData gridData = new GridData();
		gridData.horizontalIndent = convertHorizontalDLUsToPixels(20);
		completedCheckbox.setLayoutData(gridData);
		
		completedCheckbox.setEnabled(Util.isEditable(marker));
		
		Object done;
		try {
			done = marker.getAttribute(IMarker.DONE);
			completedCheckbox.setSelection(done != null
					&& done instanceof Boolean
					&& ((Boolean) done).booleanValue());
		} catch (CoreException e) {
			Policy.handle(e);
		}
	}
	/**
	 * Create the attributes area for problems
	 *