Bug 67890 [PropertiesView] Exception when entries added to properties view
bundles/org.eclipse.ui.views/src/org/eclipse/ui/views/properties/PropertySheetEntry.java
else if (object instanceof IPropertySource)
            result = (IPropertySource) object;
        else if (object instanceof IAdaptable)
            result = (IPropertySource) ((IAdaptable) object)
                    .getAdapter(IPropertySource.class);
        sources.put(object, result);
        return result;
    }
    /* (non-Javadoc)
     * Method declared on IPropertySheetEntry.
     */
    public String getValueAsString() {
        if (editValue == null)
            return "";
        ILabelProvider provider = descriptor.getLabelProvider();
        if (provider == null)
            return editValue.toString();
        String text = provider.getText(editValue);
        if(text == null)
        	return "";
        return text;
    }
    /**
     * Returns the value objects of this entry.
     *
     * @return the value objects of this entry
     * @since 3.1 (was previously private)
     */
    public Object[] getValues() {
        return values;